Free calculators for everyday decisions

Summarize monthly income, needs, wants, savings, and remaining cash with a 50/30/20 comparison.

Calculate sale price, amount saved, and combined successive discounts.

Calculate sale price, savings, and tax after a percentage discount.

Find the sales quantity and revenue that cover fixed and variable costs.

Work from cost, markup, revenue or profit to calculate your pricing figures.

Calculate straight-line, declining-balance, or sum-of-years-digits depreciation and book value for a selected year.

Calculate gross profit, margin, and markup from cost and selling price.

Compare CPC, CPM and click-through rate from one set of campaign totals.

Connect campaign spend, clicks, cost per click and completed actions.

Estimate additional funding from changes in assets, liabilities and retained earnings.

Calculate clicks as a percentage of ad impressions or solve for a missing count.

Estimate gross rating points from audience reach and exposure frequency.

Calculate customer loss per period and a simple constant-churn lifetime estimate.

Separate retained customers from new arrivals when comparing customer counts.

Estimate the overhead each billable day needs to cover.

Calculate the percentage of scheduled employee workdays lost to absence.

Measure departures against average staffing during a reporting period.

Spread a fixed cost across an output quantity and compare production volumes.

Calculate cost of goods sold from beginning inventory, purchases and ending inventory.

Compare units sold with units received for a product and period.

Calculate pre-money and post-money values for a simple equity investment.

Subtract liabilities from the liquid assets you choose to include.

Measure exits from a page relative to its pageviews over the same period.

Estimate website advertising revenue from visits and page RPM.

Measure the share of price above marginal cost.

Estimate collection days using a receivables balance or average beginning and ending balances.

Calculate revenue per employee for a consistent reporting period.

Estimate customer acquisition cost from sales spend, marketing spend and new customers.

Calculate the share of visits containing one page using a clearly defined counting method.

Express a mix of full-time and part-time staff as equivalent full-time capacity.

Compare income tax paid with earnings before tax.

Estimate total labor-hours, cost per worker and combined team labor cost.

Subtract a government benchmark yield from a corporate yield.

Annualize a single redemption gain using a simple 365-day convention.

Estimate one day of simple interest from a balance and annual rate.

Project future college costs from current annual cost, inflation, years until enrolment, and program length.

Estimate basic EPS after preferred dividends.

Evaluate the CAPM return model from beta and benchmark returns.

Subtract a modeled equity capital charge from net income.

Combine equity, debt and other claims, then subtract cash.

Express operating profit as a percentage of net sales.

Compare share price with cash flow per share.

Estimate market capitalization from share price and shares outstanding.

Compare equity share price with sales per share.

Subtract restricted and closely held shares from outstanding shares.

Calculate return on assets from net income and the asset value you choose.

Compare current assets with current liabilities or work backwards from a target ratio.

Convert periodic dividends into annual income and calculate dividend yield.

Compare earnings before interest and tax with interest expense.

Calculate return on equity and explore how income and equity affect the ratio.

Compare cost of goods sold with average inventory and estimate inventory days.

Calculate operating income and the percentage of revenue it represents.

Measure short-term liability coverage using cash, securities and receivables.

Relate share price, earnings per share and the price-to-earnings multiple.

Calculate short-term working capital, average working capital and turnover.

Compare equity market value with the equity capital invested.

Compare hedge-position value with total exposure.

Adjust a nominal return for inflation over the same period.

Convert a lease money factor to its conventional annual rate equivalent.

Estimate simple margin interest using a 360-day year.

Calculate the covariance-based hedge ratio from volatility and correlation.

Measure price gain and percentage return before dividends and costs.

Discount one future amount at a constant periodic rate.

Project a certificate-of-deposit balance from deposit, APY, term, and tax-rate assumptions.

Compare equivalent nominal interest rates across annual, monthly, daily, continuous, and other compounding periods.

Calculate compound growth with a starting balance, recurring monthly deposits, annual rate, and time.

Compare nominal interest with effective interest at different compounding frequencies.

Project savings growth from a current balance, monthly deposits, rate, and time.

Calculate simple interest, ending balance, and effective total return without compounding.

Calculate arithmetic average, compounded annual growth rate, and cumulative return from periodic percentages.

Calculate a fixed-coupon bond price and current yield from face value, coupon, market yield, maturity, and payment frequency.

Discount future cash flows and compare their present value with an initial investment.

Compare starting and ending values using an equivalent compound growth rate.

Calculate future value from present value, monthly cash flow, interest rate, and number of periods.

Compound a present lump sum to a future value using an annual return and time horizon.

Project an investment account with an initial balance, monthly deposits, annual return, and time.

Calculate periodic internal rate of return and net present value from a series of cash flows.

Project investment growth after an annual expense ratio and optional front-end sales load.

Calculate simple and discounted payback time from an initial investment and recurring cash inflow.

Discount a future lump sum to present value using an annual rate and time horizon.

Calculate return on investment, net profit, annualized return, and profit multiple.

Calculate an amortizing payment, first-month principal and interest, total interest, and payoff time.

Estimate annual percentage rate from amount received, monthly payment, term, and prepaid finance charges.

Estimate a vehicle lease payment from capitalized cost, residual, money factor, term, tax, and upfront reductions.

Estimate vehicle financing from purchase price, trade-in, down payment, sales tax, fees, and loan terms.

Estimate payment and total interest for a fixed-rate boat or marine loan.

Estimate business-loan payment, borrowing cost, fees, and payoff with optional extra principal.

Compare vehicle cash-back financing with a standard rate against a lower-rate offer without the rebate.

Estimate credit-card payoff time and interest from balance, APR, monthly payment, and extra payment.

Estimate avalanche payoff for multiple cards while preserving the entered total monthly payment.

Compare current weighted debt cost with a proposed consolidation loan after origination fees.

Compare payoff time and interest with and without an extra monthly debt payment.

Calculate front-end and back-end monthly debt-to-income ratios from gross income and required payments.

Estimate the annual rate implied by a loan amount, monthly payment, and term.

Estimate a level lease payment from asset value, residual, annual lease rate, and term.

Calculate fixed-rate loan payments, interest, total cost, and accelerated payoff with extra payments.

Estimate the periodic payment and total cost for a fixed-rate installment balance.

Compare the payment and all-in cost of an unsecured personal loan.

Estimate how long a fixed payment takes to repay a balance and how extra payments change the cost.

Estimate student-loan payments, interest, fees, and the effect of voluntary extra payments.

Express the difference between actual and potential GDP as a percentage.

Find marginal propensity to save from income and saving changes.

Measure the percentage change between two GDP values.

Estimate disposable income from income, taxes and government transfers.

Calculate an implicit GDP price index with a base value of 100.

Estimate a triangular deadweight loss from price and quantity changes.

Divide real GDP by population to estimate output per person.

Compare purchase price with the fair value of net identifiable assets.

Divide total assets by equity to find an equity multiplier.

Compare net credit sales with average accounts receivable.

Estimate EBIT from revenue and total operating costs.

Measure added cost per additional unit of output.

Express net profit as a percentage of total revenue.

Add depreciation and amortization back to operating profit.

Subtract explicit and implicit costs from revenue.

Estimate depreciated value using purchase price and useful life.

Compare revenue with average fixed assets over a period.

Calculate sales revenue from a unit price and sales quantity.

Find average variable cost from production expenses and output.

Calculate a property deposit from an entered percentage.

Find the difference between a property’s market value and sale price.

Compare a property price with its gross annual rental income.

Calculate a loan amount and its percentage of the purchase price.

Estimate a Canadian mortgage payment using nominal annual interest compounded semi-annually and monthly payments.

Calculate down payment, mortgage amount, loan-to-value ratio, and months needed to reach a savings goal.

Estimate an FHA-style mortgage payment with entered upfront and annual mortgage-insurance assumptions.

Estimate interest-only draw-period and amortizing repayment-period payments for a home-equity line of credit.

Calculate payments and interest for a lump-sum home-equity loan.

Estimate an affordable purchase price from income, debts, down payment, interest rate, and housing-cost assumptions.

Calculate mortgage payment, total interest, first payment split, and accelerated payoff.

Estimate principal-and-interest payment plus property tax, insurance, association dues, and down payment.

Estimate a UK repayment mortgage payment, total interest, deposit, and loan-to-value ratio.

Estimate mortgage payoff time, total interest, and savings from an extra monthly payment.

Estimate property cash flow, capitalization rate, cash-on-cash return, and simple net operating income.

Compare an existing mortgage with a proposed refinance, including closing costs and break-even month.

Estimate a monthly rent budget from income, existing debt, utilities, savings goal, and a chosen rent-to-income guideline.

Compare simplified multi-year net cost of renting with homeownership after equity and selling costs.

Estimate rental-property net operating income, cash flow, cap rate, and cash-on-cash return.

Estimate a VA-style mortgage payment with entered down payment, funding fee, taxes, and insurance.

Multiply monthly expenses by a chosen number of reserve months.

Split after-tax monthly income into a 50/30/20 planning example.

Compare consumption spending with disposable income.

Convert an amount with an explicit market or card exchange rate and optional foreign-exchange fee.

Estimate 2026 U.S. federal estate tax above the entered exclusion after debts, expenses, and charitable transfers.

Estimate 2026 U.S. federal ordinary income tax from filing status, gross income, and deductions.

Project future prices and purchasing power from an amount, annual inflation rate, and time.

Compare 2026 U.S. federal ordinary-income tax when two incomes are filed separately as single versus jointly.

Add or extract sales tax from a price and show the tax amount and before-tax subtotal.

Add or extract value-added tax from a price and show net, tax, and gross amounts.

Project employee and employer retirement contributions with annual growth and current-plan limits entered as assumptions.

Calculate the future value of regular deposits with optional starting principal and compound return.

Estimate a level monthly payout from an annuity balance, interest rate, and payout term.

Project traditional IRA growth and compare an illustrative taxable withdrawal after a retirement tax rate.

Estimate a level monthly pension from an account balance, payout return, and payout period.

Project retirement savings, inflation-adjusted value, and a planning withdrawal from current savings and contributions.

Estimate a required minimum distribution from prior year-end balance and an entered Uniform Lifetime Table age.

Project tax-free Roth IRA account growth from current savings, monthly contributions, return, and time.

Compare a Social Security retirement benefit estimate at claiming ages 62 through 70 from the benefit quoted at full retirement age.

Calculate a percentage commission and prices including or excluding it.

Compare current salary with the amount needed to match a past salary’s purchasing power.

Calculate tiered or flat commission, base pay, total compensation, and effective commission rate.

Convert hourly, daily, weekly, biweekly, semi-monthly, monthly, quarterly, and annual pay with holiday and vacation adjustments.

Estimate annual and per-pay take-home from salary, pre-tax deductions, 2026 federal tax, payroll tax, and a state-rate input.

Estimate a starting band and cup size from snug underbust and full-bust measurements.

Find a starting square size for the seven-eighths-inch quilting method.

Add or subtract calendar years, months, weeks, and days from a date with month-end handling.

Count elapsed and inclusive calendar days, weeks, weekdays, and weekend days between two dates.

Find the weekday, day of year, ISO week, quarter, and distance from today for any Gregorian date.

Calculate elapsed work time between clock times, including overnight shifts and an unpaid break.

Plan bedtimes or wake times around approximate 90-minute sleep cycles and a settling allowance.

Add or subtract two hour-minute-second durations and convert the result to total units.

Calculate elapsed time between two clock times, including overnight spans and break deductions.

Convert a local date and time between fixed UTC offsets, including dates that cross midnight.

Calculate expenditure-based gross domestic product and the contribution of net exports.

Encode UTF-8 text as Base64 or decode Base64 back to readable UTF-8, entirely in this browser.

Encode text for a URL component or decode percent-encoded text locally.

Estimate travel distance from available fuel and fuel economy.

Compare a service or activity cost with its duration.

Calculate fuel economy, consumption and fuel spending for a trip.

Calculate tip, total bill, and per-person split with optional sales tax separated from the tipping base.

Create a stable, playful name-match score for entertainment, with the same names always returning the same result.

Compare annual energy use with building floor area.

Estimate hot tub energy cost from average power and operating time.

Estimate energy use and electricity cost for one operating session.

Split a target mixture volume using a water-to-concentrate ratio.

Add up viewing time from episode length, episodes and seasons.

Estimate file-transfer time from file size, link speed, and protocol efficiency.

Calculate IPv4 network, broadcast, usable host range, mask, wildcard, and host capacity from CIDR notation.

Express accepted applicants as a share of all applicants.

Calculate words typed per minute before error adjustments.

Estimate average sheet thickness from a measured paper stack.

Convert typing rates using five keystrokes per standard word.

Add luggage length, width and height and express the total in inches.

Estimate download duration from file size and transfer speed, with unit choices.

Connect reading pace, daily reading time, pages and books over a chosen period.

Calculate a credit-weighted GPA from letter grades and course credits.

Calculate a current percentage and the score needed on a remaining final assessment.

Generate a high-entropy password locally with configurable length and character sets.

Estimate electricity consumption and cost from power, usage time and energy price.

Compare package prices using a common unit and see which option costs less.

Estimate the time and vehicle costs associated with a recurring commute.

Estimate driving duration from distance and average speed.

Estimate trip fuel use, total cost, and cost per traveller from distance and vehicle efficiency.

Calculate L/100 km, kilometres per litre, and miles per US gallon from distance and fuel used.

Calculate business mileage reimbursement and fuel-cost comparison for a trip.

Compare two metric tire sizes for diameter, circumference, sidewall, revolutions, and speedometer difference.

Calculate weekly hours and gross pay from a repeating shift, workdays, break, rate, and overtime settings.

Estimate room heating capacity from floor area, ceiling height, temperature rise, and insulation quality.

Calculate rectangular area, total quantity, waste allowance, square yards, and square metres.

Estimate tile count, area, and boxes from surface and tile dimensions with grout and waste allowance.

Relate concrete volume and mass using the selected material-density preset.

Calculate cylindrical or rectangular hole volume and an ordering allowance.

Estimate bricks and mortar materials using wall, joint and mix inputs.

Estimate concrete volume for a rectangular slab and add a waste allowance, with cubic-yard and bag totals.

Estimate concrete for round or rectangular columns and compare material quantities.

Estimate concrete volume and material quantities for the selected slab form.

Estimate a solid rectangular object’s volume and mass from its density.

Convert rectangular gravel-bed dimensions into material volume, tonnage and cost.

Estimate stone volume for rectangular or circular beds with an added allowance.

Estimate limestone fill volume, ordering allowance, mass and material cost.

Add up lumber volume, length and cost from actual piece dimensions.

Estimate decorative rock volume, mass and spending with an added allowance.

Estimate sand volume, mass and material cost for a rectangular fill.

Calculate mass and cost for rectangular or cylindrical solid stone pieces.

Estimate wall cladding panels, starter strip, J-channel, undersill and material cost.

Estimate asphalt volume, tonnage and material cost from a layer’s dimensions.

Estimate gravel quantity and material spending for a uniform rectangular layer.

Estimate base-course volume, mass and cost with a chosen additional-material percentage.

Calculate flooring coverage and estimate material cost with an allowance.

Estimate pavers and project costs from the area and paver dimensions.

Estimate fence post requirements from run length and spacing.

Estimate gravel volume, weight, and delivery tonnage from area, depth, and material density.

Estimate mulch volume and bag count from landscape area, depth, and bag size.

Calculate floor-area, open-space and usable-area ratios from entered areas.

Estimate bedding sand volume, mass and material cost.

Compare airflow volume per hour with the volume of a room.

Calculate board-foot volume from lumber dimensions and quantity.

Estimate plywood sheet quantities and cost from coverage and sheet dimensions.

Estimate pea gravel volume, mass and cost using a chosen bulk density.

Relate tool diameter, rotational speed, tooth count and feed per tooth.

Convert a chosen air-change target into a nominal volumetric airflow.

Relate thread pitch, measured length and threads per inch.

Find full cone depth from top diameter and included angle.

Calculate ramp geometry from a selected ratio or your own rise and run.

Convert roof rise and run into pitch and angle, or calculate an unknown dimension.

Estimate sloped roof area, roofing squares, bundles, and waste from plan dimensions and roof pitch.

Estimate riser count, actual rise, tread run, staircase length, and stringer length.

Calculate the internal capacity of a pipe and the mass of its contents.

Estimate water volume for a round pool using diameter and average depth.

Estimate wall and ceiling coverage, subtract openings and calculate panel quantities.

Estimate wall paint after subtracting doors and windows, with coats and coverage.

Estimate siding area for different wall shapes after subtracting openings.

Calculate a liquid flow rate from collected volume and elapsed time.

Estimate pool water volume and fill cost from average depth.

Convert degrees to arcminutes with editable results, unit choices and a worked example.

Convert degrees to arcseconds with editable results, unit choices and a worked example.

Estimate equivalent US, UK, and EU adult shoe sizes from one selected system.

Convert dime count to dollar value with editable results and a clear worked example.

Convert nickel count to dollar value with editable results and a clear worked example.

Convert penny count to dollar value with editable results and a clear worked example.

Convert quarter count to dollar value with editable results and a clear worked example.

Convert common length, mass, and temperature units in either metric or customary systems.

Convert whole numbers to canonical Roman numerals or Roman numerals to decimal values.

Convert cent amount to dollar value with editable results and a clear worked example.

Convert euro cent amount to euros with editable results and a clear worked example.

Convert megabit & gigabit transfer rates with editable results and a clear worked example.

Calculate data storage converter with editable inputs, reverse calculations, and unit choices.

Calculate data transfer rate converter with editable inputs, reverse calculations, and unit choices.

Calculate force converter with editable inputs, reverse calculations, and unit choices.

Calculate pressure converter with editable inputs, reverse calculations, and unit choices.

Calculate torque converter with editable inputs, reverse calculations, and unit choices.

Calculate area converter with editable inputs, reverse calculations, and unit choices.

Calculate length converter with editable inputs, reverse calculations, and unit choices.

Convert angstroms to nanometers with editable results, unit choices and a worked example.

Convert centimeters to inches with editable results, unit choices and a worked example.

Convert centimeters to meters with editable results, unit choices and a worked example.

Convert centimeters to millimeters with editable results, unit choices and a worked example.

Convert feet to centimeters with editable results, unit choices and a worked example.

Convert feet to meters with editable results, unit choices and a worked example.

Convert feet to statute miles with editable results, unit choices and a worked example.

Convert feet to yards with editable results, unit choices and a worked example.

Convert inches to centimeters with editable results, unit choices and a worked example.

Convert inches to meters with editable results, unit choices and a worked example.

Convert inches to yard length with editable results and a clear worked example.

Convert kilometers to international feet with editable results, unit choices and a worked example.

Convert kilometers to international miles with editable results and a clear worked example.

Convert kilometers to meters with editable results, unit choices and a worked example.

Convert meters to international feet with editable results, unit choices and a worked example.

Convert meters to international mile distance with editable results and a clear worked example.

Convert micrometers to thousandth-inch mils with editable results and a clear worked example.

Convert millimeters to inches with editable results, unit choices and a worked example.

Convert millimeters to international feet with editable results, unit choices and a worked example.

Convert mils to inches with editable results, unit choices and a worked example.

Convert mils to millimeters with editable results, unit choices and a worked example.

Convert nanometers to meters with editable results, unit choices and a worked example.

Convert avoirdupois ounces to kilograms with editable results and a clear worked example.

Convert decagrams to grams with editable results and a clear worked example.

Convert grams to avoirdupois pounds with editable results and a clear worked example.

Convert kilograms to fourteen-pound stones with editable results and a clear worked example.

Convert kilograms to international pounds with editable results and a clear worked example.

Convert micrograms to milligrams with editable results and a clear worked example.

Convert milligrams to pounds with editable results, unit choices and a worked example.

Convert ounces to avoirdupois pounds with editable results, unit choices and a worked example.

Convert pounds to grams with editable results, unit choices and a worked example.

Convert pounds to kilograms with editable results, unit choices and a worked example.

Convert pounds to mass ounces with editable results, unit choices and a worked example.

Calculate frequency converter with editable inputs, reverse calculations, and unit choices.

Calculate fuel economy converter with editable inputs, reverse calculations, and unit choices.

Calculate speed converter with editable inputs, reverse calculations, and unit choices.

Calculate time unit converter with editable inputs, reverse calculations, and unit choices.

Convert crores to lakhs with editable results and a clear worked example.

Convert crores to millions with editable results and a clear worked example.

Convert millions to lakhs with editable results and a clear worked example.

Convert millions to short-scale billions with editable results and a clear worked example.

Convert millions to thousands & full numbers with editable results and a clear worked example.

Convert whole numbers to millions with editable results and a clear worked example.

Convert whole numbers to short-scale billions with editable results and a clear worked example.

Convert ksi to psi with editable results, unit choices and a worked example.

Convert standard atmospheres to pascals with editable results, unit choices and a worked example.

Calculate energy converter with editable inputs, reverse calculations, and unit choices.

Calculate power converter with editable inputs, reverse calculations, and unit choices.

Calculate temperature converter with editable inputs, reverse calculations, and unit choices.

Convert celsius to fahrenheit with editable results, unit choices and a worked example.

Convert centigrade & celsius temperature names with editable results and a clear worked example.

Convert kelvin to celsius with editable results, unit choices and a worked example.

Convert kelvin to fahrenheit with editable results, unit choices and a worked example.

Convert hours to minutes & seconds with editable results and a clear worked example.

Convert minutes to hour duration with editable results and a clear worked example.

Convert minutes to seconds with editable results, unit choices and a worked example.

Convert months to years with editable results, unit choices and a worked example.

Convert seconds to 24-hour days with editable results, unit choices and a worked example.

Convert seconds to hours with editable results, unit choices and a worked example.

Convert years to ten-year decades with editable results and a clear worked example.

Calculate volume converter with editable inputs, reverse calculations, and unit choices.

Calculate weight and mass converter with editable inputs, reverse calculations, and unit choices.

Calculate density converter with editable inputs, reverse calculations, and unit choices.

Convert cc, milliliters & liters with editable results, unit choices and a worked example.

Convert cubic centimeters to liters with editable results, unit choices and a worked example.

Convert cubic feet to metric volume with editable results and a clear worked example.

Convert liters to centiliters with editable results and a clear worked example.

Convert liters to cubic centimeters with editable results and a clear worked example.

Convert milliliters to cubic centimeters with editable results, unit choices and a worked example.

Convert milliliters to microliters with editable results, unit choices and a worked example.

Perform exact arithmetic on integers larger than JavaScript's ordinary safe-number range.

Perform exact arithmetic on binary integers and convert the result to decimal and hexadecimal.

Perform exact arithmetic on hexadecimal integers and convert the result to decimal and binary.

Convert decimal numbers to normalized scientific and engineering notation.

Calculate straight-line distance, displacement, midpoint, and coordinate differences between two points.

Find slope, distance, midpoint, line equation, and angle from two Cartesian points.

Evaluate arithmetic with parentheses, powers, percentages, and standard operator precedence.

Raise any real base to an integer or fractional exponent and show reciprocal forms for negative powers.

Calculate logarithms with any positive base, including common and natural logarithms.

Solve ax² + bx + c = 0 and report real or complex roots, the discriminant, and vertex.

Calculate square, cube, or nth roots, including real odd roots of negative numbers.

Evaluate scientific expressions with powers, roots, trigonometry, logarithms, constants, and factorials.

Add, subtract, multiply, or divide two fractions and reduce the answer to lowest terms.

Compare an observed value with an accepted value and calculate absolute and signed percent error.

Solve percent-of, percent-ratio, and percentage-change questions with the formula shown.

Simplify a ratio, convert it to fractions and percentages, and scale it to a chosen total.

Calculate area and perimeter for rectangles, circles, triangles, trapezoids, and ellipses.

Find diameter, circumference, area, and equations from a circle radius.

Find the hypotenuse and other properties of a right triangle from its two legs.

Solve all sides, acute angles, area, and perimeter from two right-triangle legs.

Calculate total and lateral surface area for common solid shapes.

Solve a triangle from three side lengths, including area, perimeter, angles, and classification.

Find the volume and surface area of common three-dimensional shapes.

Add, subtract, multiply, transpose, or find the determinant of matrices up to 8 by 8.

List all positive factors shared by two or more whole numbers.

List every positive factor and factor pair for a whole number.

Find the greatest common factor of two or more whole numbers.

Find the least common multiple of two or more whole numbers.

Break a whole number into prime factors and show exponential notation.

Divide whole numbers and show quotient, remainder, decimal result, and the division identity.

Analyze a sequence for arithmetic or geometric patterns and project its next five terms.

Generate one or more random integers or decimals within an inclusive range.

Round a number to decimal places or significant figures and compare floor, ceiling, and truncation.

Calculate the remaining amount, elapsed half-lives, and decay constant for exponential decay.

Calculate ordered permutations and unordered combinations for n objects chosen r at a time.

Calculate arithmetic mean, median, sum, count, minimum, and maximum for a list of numbers.

Estimate a normal-theory confidence interval for a mean from a sample mean, deviation, and size.

Find the mean, median, mode, range, sum, and count of a list of numbers.

Convert a z statistic to left-tailed, right-tailed, and two-tailed normal-distribution p-values.

Calculate event probability, odds, complements, and independent two-event combinations.

Estimate a survey sample size from confidence level, margin of error, population, and expected proportion.

Calculate population and sample standard deviation, variance, mean, and count for a data set.

Summarize a data set with centre, spread, variance, standard deviation, and sorted values.

Standardize a value using a population mean and standard deviation, then estimate its percentile.

Estimate circumference-based body-fat percentage using the established neck, waist, hip, and height equations.

Calculate adult body mass index, CDC weight category, and the weight range corresponding to BMI 18.5 through 24.9.

Estimate body-fat percentage with the circumference-based U.S. Navy method and calculate fat and lean mass.

Compare bust, waist, and hip proportions to describe a geometric body-shape pattern and waist-to-hip ratio.

Calculate the adult weight interval corresponding to BMI 18.5 through 24.9 for a given height.

Compare four commonly cited height-based reference-weight formulas and the adult healthy-BMI range.

Compare Boer, Hume, and James lean-body-mass estimates from height, weight, and sex.

Calculate current BMI and reference weights for BMI 18.5 and the historically cited 17.5 threshold.

Compare current weight with adult BMI 25 and 30 reference thresholds for the same height.

Estimate blood alcohol concentration from standard-drink alcohol mass, body weight, sex coefficient, and elapsed time.

Estimate body surface area with the Mosteller, Du Bois, and Haycock equations.

Estimate adult glomerular filtration rate with the race-free 2021 CKD-EPI creatinine equation.

Estimate basal metabolic rate and maintenance energy with the Mifflin-St Jeor equation.

Estimate daily calories to maintain, lose, or gain weight from the Mifflin-St Jeor resting-energy equation.

Estimate calorie targets and daily carbohydrate allowances for weight maintenance, loss, and gain from age, sex, height, weight, and activity.

Estimate calorie targets, total fat range, and saturated-fat limits for weight maintenance, loss, and gain.

Estimate the December 2015 to November 2021 food points value from calories, sugar, saturated fat, and protein.

Estimate daily protein, carbohydrate, and fat targets from energy needs, goal, and a chosen macro split.

Estimate daily protein recommendations from body weight and calorie needs using ADA, CDC, and WHO reference methods.

Estimate total daily energy expenditure from resting energy and an activity multiplier.

Estimate a child's mid-parental adult height range from biological-parent heights and the sex adjustment used by the method.

Estimate exercise energy expenditure from activity MET value, body weight, and duration.

Estimate maximum heart rate and training zones with both percent-maximum and Karvonen heart-rate-reserve methods.

Estimate likely conception and fertile-window dates from a period date, due date, or known birth date.

Estimate a pregnancy due date from last menstrual period, conception, or embryo-transfer date.

Estimate ovulation date, fertile window, and next period from the last period and typical cycle length.

Project upcoming period and ovulation dates from a typical cycle and period length.

Estimate due date, conception window, trimester dates, and current gestational age from the last menstrual period.

Estimate conception and fertile-window dates from a due date or last menstrual period.

Compare current pregnancy weight gain with Institute of Medicine reference ranges based on pre-pregnancy BMI.

Estimate appliance energy use and cost from power, daily runtime, days, and electricity rate.

Calculate voltage, current, resistance, and power from any two selected electrical values.

Decode a four-band resistor value from colour digits, multiplier, and tolerance.

Estimate two-conductor copper or aluminum circuit voltage drop from length, current, voltage, and wire area.

Calculate engine horsepower and kilowatts from torque and rotational speed.

Calculate mechanical horsepower and watts from force, travel distance, and elapsed time.

Calculate density from mass and volume, with common SI and metric conversions.

Calculate mass from density and volume, with grams, kilograms, and pounds.

Calculate speed from distance and time with km/h, m/s, mph, and pace conversions.

Calculate gravitational weight force from mass and local gravitational acceleration.

Calculate dew point and a plain-language humidity comfort description from temperature and relative humidity.

Estimate apparent temperature from air temperature and relative humidity with the NOAA regression.

Calculate the North American wind-chill index from air temperature and wind speed.

Calculate solution molarity, millimolar concentration, and amount from moles and volume.

Calculate molar mass from a chemical formula, including grouped formulas such as Ca(OH)2.

Estimate one-repetition maximum and training loads from weight lifted and completed repetitions.

Calculate running pace, speed, and projected finish times from distance and elapsed time.

Estimate a World Handicap System-style index from recent score differentials.