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1822 apps · Showing 865–960
Data & Calculators
1822 appsData & Calculators: View & Inspect
Data & Calculators: Clean & Organize
CSV Cleaner
Trim extra spaces, remove empty rows and columns, and repair uneven CSV data in one private pass.
CSV Column Picker
Choose, reorder, and export only the CSV columns you want while leaving the original file untouched.
CSV Sorter
Sort a CSV by any column from A to Z, Z to A, smallest to largest, or largest to smallest.
Remove Duplicate CSV Rows
Find repeated CSV rows by every column or the columns you choose, then keep one clear copy of each row.
Data & Calculators: Convert
CSV Delimiter Converter
Change commas, tabs, semicolons, or pipes without breaking quoted text, commas inside cells, or line breaks.
CSV to JSON Converter
Convert CSV or TSV rows into clean JSON objects, with each heading used as a clear field name.
JSON to CSV Converter
Convert a JSON object or list of objects into a spreadsheet-ready CSV with one column for every field.
Data & Calculators: Combine & Split
Data & Calculators: Date Calculators
Age Calculator
Find an exact age in years, months, and days, plus the next birthday and useful age milestones.
Business-Day Calculator
Count workdays or add business days using your workweek and a custom holiday list.
Date Difference Calculator
Measure the exact time between two moments in calendar units, hours, minutes, and seconds.
Days Between Dates Calculator
Count calendar days between two dates with clear start-day and end-day inclusion choices.
Data & Calculators: Everyday Math
Data & Calculators: Clocks & Timers
Countdown Timer
Count down a duration or a future date with quick presets, pause controls, and an optional finish sound.
Stopwatch
Time anything with a precise stopwatch, lap splits, best and slowest laps, and keyboard controls.
World Clock & Meeting Planner
Compare live local times around the world and find a meeting time that lands on the right day.
Data & Calculators: Business Pricing
Data & Calculators: Business Calculators
Camp Pricing & Break-Even Calculator
Try different prices and group sizes. See how many bookings could cover your costs.
Massage Room Rent vs Commission Calculator
Compare room rent and commission across working weeks, recovered no-show fees, full costs, hourly earnings, and client break-even.
No-Show Cost, Deposit & Cancellation Window Calculator
Calculate revenue and time lost to no-shows, then optimize a practical deposit, cancellation window, and the net ROI of reminders or a waitlist.
Data & Calculators: Averages & Centers
Arithmetic Mean Finder
Add a list of numbers and divide by how many values it has.
Geometric Mean Finder
Find the geometric mean of positive numbers such as growth factors.
Harmonic Mean Finder
Find the harmonic mean of positive rates or ratios.
Log Average Finder
Find an average in log space for positive values that span a wide range.
Most Common Number Finder
Find the number that appears most often in a list.
Number List Extent Finder
Find both ends of a number list and the distance between them.
Number List Median Finder
Sort a number list and find the value in its middle.
Number List Product Finder
Multiply all numbers in a list and show the final product.
Precise Number List Sum
Add many values with a method that reduces floating-point rounding loss.
Root Mean Square Finder
Square, average, and take the root to measure the size of changing values.
Data & Calculators: Biology Calculators
Cell Population Doubling Time & Continuous Growth Rate
Calculate exponential doubling time and continuous growth rate from a rising cell count or concentration measured over a positive time interval.
Cell Suspension Dilution: Concentration & Volume
Balance cell concentration and volume before and after dilution using conservation of cell count and compatible volume units.
Daily Plant Light Budget from PPFD & Duration
Calculate a daily light integral from measured photon flux and daily exposure, or find the light duration or PPFD needed for a specified photon budget.
DNA Insert Mass from Vector Mass & Molar Ratio
Calculate insert DNA mass from vector mass, fragment lengths and a chosen insert-to-vector molar ratio, with bp/kb and mass unit choices.
Exponential Bacterial Growth & Doubling Time
Relate initial and final populations, elapsed time, hourly fractional growth and doubling time during ideal exponential growth.
Field Coverage from Width, Speed & Overlap
Estimate area covered per hour and moving time from implement width, travel speed and overlap, with acre and hectare conversion.
Log Reduction, Surviving Count & Percent Reduction
Convert positive before-and-after counts into decimal-log and percentage reductions, including inverse count calculations.
Observed Mutant Fraction of a Population
Calculate observed mutant frequency from mutant and total counts, or recover a count from the fraction.
qPCR Standard-Curve Efficiency & Amplification Factor
Convert a negative standard-curve slope to amplification factor and apparent qPCR efficiency, or recover slope from the factor.
Data & Calculators: Camp Operations
Data & Calculators: Charts & Data
Chart Specification Playground
Edit a Vega-Lite chart in JSON. Preview changes, check errors and download the chart as SVG or its settings as JSON.
Custom Infographic Builder
Make an infographic from CSV data. Choose bars, dots or number cards, edit the artwork and download SVG or PNG images.
Data Quality Visualizer
Check CSV data for missing values, duplicate rows and unusual numbers. Explore charts and download a column report.
Data Story Slide Builder
Turn data into a slide presentation. Add charts and notes, arrange slides and download a presentation that opens in a browser.
Declarative Chart Builder
Build a Vega-Lite chart from CSV data. Choose columns, chart marks and summaries, then save the chart and its settings.
Function Graphing Pad
Plot up to six math functions together. Change values and graph ranges, zoom in and download the chart.
Hierarchical Data Explorer
Show nested JSON as a treemap, sunburst or icicle chart. Open each branch to explore its values and save an image.
Interactive Chart Studio
Make bar, line, scatter, pie and other charts from CSV data. Choose columns, group values and save your chart project.
Measured Data Surface Viewer
Turn x, y and z measurements into a 3D surface. Rotate the view, add contour lines and download the chart.
Personal History Timeline
Make a timeline of personal events. Add dates, groups and notes, then search your history and save an editable copy.
Personal Progress Dashboard
Track reading, habits and projects with charts. Add entries, set targets and save a copy of your dashboard.
Project Milestone Viewer
See project milestones on a timeline. Add dates and notes, group related work and focus on a chosen date range.
Sensor Comparison Dashboard
Compare sensor readings on shared or separate charts. Pick a time range and review missing values and number summaries.
Small Multiples Explorer
Compare groups of data in matching charts. Use histograms, box plots or violin plots with the same number scale.
Time-Series Log Viewer
Plot timestamped CSV measurements over time. Zoom into a range, spot gaps and download a summary of the selected data.
Data & Calculators: Chemistry Calculators
Acid pKa from Ka or Buffer Measurements
Calculate pKa from a positive acid dissociation constant or estimate it separately from buffer pH and component concentrations.
Actual Yield, Theoretical Yield & Recovery Percentage
Relate measured product mass, theoretical product mass and their percentage ratio.
Air-to-Fuel Mass Ratio & Fuel Presets
Relate air mass, fuel mass and their ratio with fixed fuel presets or a custom air-to-fuel ratio.
Arrhenius Rate, Temperature & Activation Energy
Solve the Arrhenius relation for activation energy, first-order rate constant, frequency factor or absolute temperature with reversible unit conversion.
Avogadro Atoms, Moles & Sample Mass
Convert between atom count, amount in moles and sample mass using the exact Avogadro constant and your entered molar mass.
Binary Mixture Mole Fraction & Molality
Find solute mole fraction and mole percent in a two-component mixture, with optional molality from solvent molar mass.
Buffer pH, Acid–Base Ratio & pKa
Solve the Henderson–Hasselbalch relationship between weak-acid buffer pH, pKa and the conjugate-base-to-acid concentration ratio.
Calcium & Magnesium to CaCO₃ Water Hardness
Estimate calcium-and-magnesium hardness as CaCO₃, classify the result, or recover one ion concentration from measured hardness and the other ion.
Chromatography Bed, Flow & Residence Time
Calculate nominal bed residence time from linear flow velocity or cylindrical bed dimensions and volumetric flow.
COD from Blank and Sample Titrations
Calculate an uncorrected titrimetric chemical oxygen demand from blank/sample FAS volumes, normality and sample aliquot volume.
Conserved-Solute Concentration & Volume
Solve the concentration-volume balance for a fixed amount of solute before and after a volume change.
Cubic Crystal Plane Spacing & Miller Indices
Calculate interplanar spacing for a cubic lattice from its lattice constant and signed integer Miller indices, with material presets.
Dilute-Water pH, pOH & Hydrogen-Ion Estimate
Convert pH, pOH and approximate hydrogen-ion concentration in dilute water using pKw = 14 near 25°C.
Enzyme Specific Activity & Required Mass
Find enzyme preparation mass from its specific activity, a target activity per volume and final volume.
Equivalent Mass, Concentration & Solution Volume
Relate reaction-specific equivalent mass to solute mass, final solution volume and equivalent concentration.
Formula Hydrogen Deficiency & Unsaturation
Calculate the hydrogen-deficiency index from carbon, hydrogen, nitrogen and halogen atom counts.
Galvanic Cell Reduction-Potential Difference
Subtract anode reduction potential from cathode reduction potential for a positive galvanic-cell potential.
Gibbs Energy from Enthalpy, Entropy & Temperature
Relate Gibbs energy change, enthalpy change, entropy change and absolute temperature on a common process basis.
Gibbs Phase Rule with Fixed Conditions
Calculate equilibrium degrees of freedom from independent components and phases, with zero, one or two fixed temperature/pressure constraints.
Graham’s Gas-Rate & Molar-Mass Comparison
Compare ideal gas effusion rates and molar masses using Graham’s inverse-square-root relationship.
Ideal-Gas Sample Molar Mass
Estimate a gas sample’s molar mass from mass, absolute pressure, volume and temperature using the ideal-gas law.
Isoelectric Point from Two Bracketing pKa Values
Estimate pI from the two acid-dissociation pKa values surrounding a neutral species, or recover a missing pKa using the same two-step charge model.
Limiting-Reactant Stoichiometric Product Yield
Calculate theoretical product amount and mass from a known limiting reactant and balanced reaction coefficients.
Mass Concentration & Molar Concentration
Convert positive mass-per-volume concentration to amount-per-volume concentration using the solute molar mass.
Mass Percent & Density to Molar Concentration
Convert mass percentage to molarity or solve a related quantity using solution density and a preset or custom solute molar mass.
Mass-Fraction ppm to Molarity at 1 kg/L
Convert mass-based parts per million or billion to molarity at the fixed solution-density assumption of 1 kg/L.
Molecular-Orbital Electron Counts & Bond Order
Find molecular-orbital bond order from bonding and antibonding electron counts, including zero net bond order.
Nominal Tank Detention Time from Volume & Flow
Estimate nominal hydraulic detention time from operating liquid volume and flow, or derive volume from constant base area and liquid depth.
Optical Absorbance, Concentration & Transmission
Relate decadic absorbance, percent transmittance, concentration, optical path and molar absorption coefficient.
Organic Formula Degree of Unsaturation
Calculate double-bond equivalents from carbon, hydrogen, nitrogen and halogen counts under the standard neutral-molecule valence model.
Q10 Rate Change per Ten Degrees
Calculate the Q10 temperature coefficient from two positive rates at different temperatures, with reversible rate and temperature solving.
Radionuclide Activity, Specific Activity & Half-Life
Calculate activity and specific activity from the mass, molar mass and half-life of a single radionuclide using the exact Avogadro constant.
Reaction Equivalent Concentration from Mass & Volume
Calculate reaction-specific equivalents per volume from solute mass and a stated equivalents-per-mass factor.
Reaction Product Mass & Percent Yield
Calculate percent yield from actual and theoretical product masses, or solve either mass with selectable mass units.
Sample Mass, Moles & Molecule Count
Convert sample mass, molar mass, amount of substance and molecule count with scientific notation and selectable mass and mole units.
Solute Amount, Target Concentration & Final Volume
Find final solution volume from a known solute amount and desired amount concentration.
Solute Mass, Solution Volume & Molarity
Relate solute mass, molar mass and final solution volume to mass concentration and molarity.
Solute Moles, Solvent Mass & Molality
Calculate molality from solute amount and solvent mass, with an optional solute-mass and molar-mass calculation.