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3633 apps · Showing 1921–2016
Data & Calculators
1770 appsData & Calculators: Chemistry Calculators
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.
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.
Solution Boiling Elevation, Molality & Particle Factor
Estimate ideal boiling-point elevation from solvent properties, molality and van’t Hoff factor, with corrected interval and reciprocal-mass units.
Solution Freezing Point, Molality & Particle Factor
Estimate freezing-point depression for a dilute solution using solvent presets or a custom cryoscopic constant and particle factor.
Solution Osmotic Pressure & Molar Concentration
Estimate osmotic pressure from concentration, temperature, particle factor and osmotic coefficient, or derive concentration from mass and solution volume.
Stock, Diluent & Total-Volume Dilution Ratios
Compare total-to-stock and diluent-to-stock ratios for positive volumes under an additive-volume assumption.
Tank Volume, Flow & Hydraulic Retention Time
Estimate nominal hydraulic retention time from working liquid volume and steady flow, with area-depth volume calculation.
Temperature–Vapor Pressure & Raoult’s Law
Relate two equilibrium vapor pressures and temperatures with constant vaporization enthalpy, or calculate an ideal solution’s solvent partial pressure.
Data & Calculators: Construction Calculators
Area & Depth to Cubic Yards
Calculate uniform-layer volume from area and depth, with square-foot, inch and cubic-yard defaults and other retained units.
Asphalt Layer Tonnage & Cost Calculator
Estimate asphalt volume, tonnage and material cost from a layer’s dimensions.
Baluster Aggregate Count from Clear Span and Gap Target
Baluster Aggregate Count from Clear Span and Gap Target. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Board-on-Board Fence Pickets, Rails and Post Estimate
Board-on-Board Fence Pickets, Rails and Post Estimate. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.
Bolt Torque, Clamp Force & Effective Nut Factor
Explore torque and clamp force using a selected nut factor, nominal diameter and an explicit percentage adjustment.
Brick Quantity & Mortar Materials Calculator
Estimate bricks and mortar materials using wall, joint and mix inputs.
Building Floor & Land Area Ratios Calculator
Calculate floor-area, open-space and usable-area ratios from entered areas.
Bulk Material Tonnage & Allowance Calculator
Estimate bulk material mass and cost with a chosen extra-order percentage.
Chicken Coop Area by Flock & Daytime Access
Add floor-area allowances for standard-size and bantam chickens under three stated daytime-access assumptions.
Circular Arc Chord & Sagitta Calculator
Find the minor-arc sagitta from a circular radius and straight chord width, with an illustrated measurement guide.
Circular Pen Perimeter & Panel Equivalents
Estimate a circular pen’s perimeter from diameter and divide it by nominal panel length to obtain panel equivalents.
Circular Pipe Internal Capacity & Liquid Mass
Calculate the internal volume of a uniform circular pipe and the mass of a filling liquid using its density.
Concrete Column Volume & Mix Calculator
Estimate concrete for round or rectangular columns and compare material quantities.
Concrete Slab Volume & Material Calculator
Estimate concrete volume and material quantities for the selected slab form.
Concrete Volume, Density & Mass Calculator
Relate concrete volume and mass using the selected material-density preset.
Crushed Stone Volume & Fixed-Density Weight
Estimate rectangular or round/oval stone volume, extra allowance and weight at a stated fixed bulk density.
Cutting Speed, Spindle & Feed Calculator
Relate tool diameter, rotational speed, tooth count and feed per tooth.
Deck Board Area Allowance & Fastener Budget
Estimate boards or square profiles from deck area with the captured 10% allowance, plus area-based fastener counts and entered material cost.
Driveway Gravel Volume, Mass & Cost Calculator
Estimate gravel quantity and material spending for a uniform rectangular layer.
Drywall Area & Panel Quantity Calculator
Estimate wall and ceiling coverage, subtract openings and calculate panel quantities.
Eight-Mode Area & Square-Meter Converter
Calculate area for rectangles, squares, circles, triangles and regular polygons, or convert a supplied area between units.
Elliptical Arch Rise and Focal Marking Positions
Elliptical Arch Rise and Focal Marking Positions. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Fastener Shank–Head Midpoint Hole Diameter
Calculate the diameter halfway between a positive fastener shank and a larger head in this geometric model.
Fence Post Length Split by a Chosen Embedment Ratio
Fence Post Length Split by a Chosen Embedment Ratio. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Fence Posts & Spacing Calculator
Estimate fence post requirements from run length and spacing.
Fence Stain Coverage, Coats & Material Cost
Estimate liquid stain and entered material cost for one or both fence faces, with one-coat, two-coat and box-fence assumptions.
Flooring Area & Material Cost Calculator
Calculate flooring coverage and estimate material cost with an allowance.
Flooring Area, Waste Allowance & Material Cost
Calculate rectangular room area, extra material for waste, and material-only cost with area and currency unit selectors.
Gravel Bed Volume, Tonnage & Budget Calculator
Convert rectangular gravel-bed dimensions into material volume, tonnage and cost.
Hollow Pipe Mass, Wall Thickness and Mass per Length
Hollow Pipe Mass, Wall Thickness and Mass per Length. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.
Ideal Conical Recess Depth Calculator
Find full cone depth from top diameter and included angle.
Landscape Stone Volume & Allowance Calculator
Estimate stone volume for rectangular or circular beds with an added allowance.
Leaning Ladder Geometry and Rail Length Beyond Support
Leaning Ladder Geometry and Rail Length Beyond Support. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Limestone Fill, Allowance & Cost Calculator
Estimate limestone fill volume, ordering allowance, mass and material cost.
Lumber Board Feet & Cost
Calculate lumber volume in board feet from board dimensions and count, then multiply by a supplied price per board foot.
Lumber Board Feet & Cost Calculator
Calculate board-foot volume from lumber dimensions and quantity.
Lumber Piece Volume & Order Cost Calculator
Add up lumber volume, length and cost from actual piece dimensions.
Measured Liquid Flow Rate Calculator
Calculate a liquid flow rate from collected volume and elapsed time.
Metal Roof Area & Panel Cost Lower Bound
Estimate roof area from measured surface dimensions or footprint and pitch, then calculate an area-only panel-count and material-cost lower bound.
Mortar Bags from Entered Brick or Block Yield
Round mortar bags up from masonry count and entered coverage per bag, then calculate total dry bag mass.
Paver Bedding Sand Order Calculator
Estimate bedding sand volume, mass and material cost.
Paver Quantity & Installation Cost Calculator
Estimate pavers and project costs from the area and paver dimensions.
Pea Gravel Volume, Weight & Cost Calculator
Estimate pea gravel volume, mass and cost using a chosen bulk density.
Pipe Capacity & Liquid Mass Calculator
Calculate the internal capacity of a pipe and the mass of its contents.
Pipe Rolling Offset, Centerline Travel and Run
Pipe Rolling Offset, Centerline Travel and Run. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Plywood Coverage, Sheets & Cost Calculator
Estimate plywood sheet quantities and cost from coverage and sheet dimensions.
Plywood Whole-Sheet Area Estimate and Material Budget
Plywood Whole-Sheet Area Estimate and Material Budget. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.
Post Hole Volume & Order Calculator
Calculate cylindrical or rectangular hole volume and an ordering allowance.
Post-Hole Concrete Volume with Three-Times Hole Dimensions
Post-Hole Concrete Volume with Three-Times Hole Dimensions. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.
Ramp Rise, Run & Slope Calculator
Calculate ramp geometry from a selected ratio or your own rise and run.
Rectangular & Oval Pool Fill Calculator
Estimate pool water volume and fill cost from average depth.
Rectangular Fence Length with Optional Gate Opening
Rectangular Fence Length with Optional Gate Opening. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.
Rectangular or Circular Coating Volume
Estimate geometric mixed-coating volume from a rectangular or circular surface and a uniform entered thickness.
Rectangular Paving Pieces & Installed Cost Calculator
Estimate whole paver counts, material spending and area-based installation costs.
Rectangular Rebar Grid Length & Stock Lower Bound
Estimate two-direction rebar grid length from slab dimensions, edge offsets and maximum spacing, with a clearly labeled stock-length lower bound.
Rectangular Solid Volume & Mass Calculator
Estimate a solid rectangular object’s volume and mass from its density.
Rectangular Square-Yard Area & Cost Calculator
Convert rectangular dimensions into square yards and estimate cost from an area price.
River Rock Bed & Allowance Budget Calculator
Estimate decorative rock volume, mass and spending with an added allowance.
Road Base Ordering Allowance Calculator
Estimate base-course volume, mass and cost with a chosen additional-material percentage.
Roof Pitch, Angle & Rise Calculator
Convert roof rise and run into pitch and angle, or calculate an unknown dimension.
Roof Rise, Run, Rafter & Pitch Geometry
Relate rise, horizontal run, geometric rafter length, angle, percentage slope and rise per 12 units of run.
Roof Slope Area & Entered Unit Cost
Convert horizontal projected area into a uniform-pitch surface area and apply an entered price per area unit.
Room Airflow Change Rate Calculator
Compare airflow volume per hour with the volume of a room.
Room Paint Quantity & Cost Calculator
Estimate wall paint after subtracting doors and windows, with coats and coverage.
Room Transmission Heat Loss with Fixed Opening Sizes
Estimate a room’s simplified transmission heat loss using wall U-value, captured window and door assumptions, and indoor/outdoor temperatures.
Room Volume & Required Airflow Calculator
Convert a chosen air-change target into a nominal volumetric airflow.