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3633 apps · Showing 1921–2016

Data & Calculators

1770 apps

Data & Calculators: Chemistry Calculators

Calculator · CalculateEnzyme Specific Activity & Required MassFind enzyme preparation mass from its specific activity, a target activity per volume and final volume.Calculator · CalculateEquivalent Mass, Concentration & Solution VolumeRelate reaction-specific equivalent mass to solute mass, final solution volume and equivalent concentration.Calculator · CalculateFormula Hydrogen Deficiency & UnsaturationCalculate the hydrogen-deficiency index from carbon, hydrogen, nitrogen and halogen atom counts.Calculator · CalculateGalvanic Cell Reduction-Potential DifferenceSubtract anode reduction potential from cathode reduction potential for a positive galvanic-cell potential.Calculator · CalculateGibbs Energy from Enthalpy, Entropy & TemperatureRelate Gibbs energy change, enthalpy change, entropy change and absolute temperature on a common process basis.Calculator · CalculateGibbs Phase Rule with Fixed ConditionsCalculate equilibrium degrees of freedom from independent components and phases, with zero, one or two fixed temperature/pressure constraints.Calculator · CalculateGraham’s Gas-Rate & Molar-Mass ComparisonCompare ideal gas effusion rates and molar masses using Graham’s inverse-square-root relationship.Calculator · CalculateIdeal-Gas Sample Molar MassEstimate a gas sample’s molar mass from mass, absolute pressure, volume and temperature using the ideal-gas law.Calculator · CalculateLimiting-Reactant Stoichiometric Product YieldCalculate theoretical product amount and mass from a known limiting reactant and balanced reaction coefficients.Calculator · CalculateMass Concentration & Molar ConcentrationConvert positive mass-per-volume concentration to amount-per-volume concentration using the solute molar mass.Calculator · CalculateMass Percent & Density to Molar ConcentrationConvert mass percentage to molarity or solve a related quantity using solution density and a preset or custom solute molar mass.Calculator · CalculateMass-Fraction ppm to Molarity at 1 kg/LConvert mass-based parts per million or billion to molarity at the fixed solution-density assumption of 1 kg/L.Calculator · CalculateMolecular-Orbital Electron Counts & Bond OrderFind molecular-orbital bond order from bonding and antibonding electron counts, including zero net bond order.Calculator · CalculateNominal Tank Detention Time from Volume & FlowEstimate nominal hydraulic detention time from operating liquid volume and flow, or derive volume from constant base area and liquid depth.Calculator · CalculateOptical Absorbance, Concentration & TransmissionRelate decadic absorbance, percent transmittance, concentration, optical path and molar absorption coefficient.Calculator · CalculateOrganic Formula Degree of UnsaturationCalculate double-bond equivalents from carbon, hydrogen, nitrogen and halogen counts under the standard neutral-molecule valence model.Calculator · CalculateQ10 Rate Change per Ten DegreesCalculate the Q10 temperature coefficient from two positive rates at different temperatures, with reversible rate and temperature solving.Calculator · CalculateRadionuclide Activity, Specific Activity & Half-LifeCalculate activity and specific activity from the mass, molar mass and half-life of a single radionuclide using the exact Avogadro constant.Calculator · CalculateReaction Equivalent Concentration from Mass & VolumeCalculate reaction-specific equivalents per volume from solute mass and a stated equivalents-per-mass factor.Calculator · CalculateReaction Product Mass & Percent YieldCalculate percent yield from actual and theoretical product masses, or solve either mass with selectable mass units.Calculator · CalculateSample Mass, Moles & Molecule CountConvert sample mass, molar mass, amount of substance and molecule count with scientific notation and selectable mass and mole units.Calculator · CalculateSolute Amount, Target Concentration & Final VolumeFind final solution volume from a known solute amount and desired amount concentration.Calculator · CalculateSolute Mass, Solution Volume & MolarityRelate solute mass, molar mass and final solution volume to mass concentration and molarity.Calculator · CalculateSolute Moles, Solvent Mass & MolalityCalculate molality from solute amount and solvent mass, with an optional solute-mass and molar-mass calculation.Calculator · CalculateSolution Boiling Elevation, Molality & Particle FactorEstimate ideal boiling-point elevation from solvent properties, molality and van’t Hoff factor, with corrected interval and reciprocal-mass units.Calculator · CalculateSolution Freezing Point, Molality & Particle FactorEstimate freezing-point depression for a dilute solution using solvent presets or a custom cryoscopic constant and particle factor.Calculator · CalculateSolution Osmotic Pressure & Molar ConcentrationEstimate osmotic pressure from concentration, temperature, particle factor and osmotic coefficient, or derive concentration from mass and solution volume.Calculator · CalculateStock, Diluent & Total-Volume Dilution RatiosCompare total-to-stock and diluent-to-stock ratios for positive volumes under an additive-volume assumption.Calculator · CalculateTank Volume, Flow & Hydraulic Retention TimeEstimate nominal hydraulic retention time from working liquid volume and steady flow, with area-depth volume calculation.Calculator · CalculateTemperature–Vapor Pressure & Raoult’s LawRelate two equilibrium vapor pressures and temperatures with constant vaporization enthalpy, or calculate an ideal solution’s solvent partial pressure.

Data & Calculators: Construction Calculators

Calculator · CalculateArea & Depth to Cubic YardsCalculate uniform-layer volume from area and depth, with square-foot, inch and cubic-yard defaults and other retained units.Calculator · CalculateAsphalt Layer Tonnage & Cost CalculatorEstimate asphalt volume, tonnage and material cost from a layer’s dimensions.Calculator · CalculateBaluster Aggregate Count from Clear Span and Gap TargetBaluster Aggregate Count from Clear Span and Gap Target. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculateBoard-on-Board Fence Pickets, Rails and Post EstimateBoard-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.Calculator · CalculateBolt Torque, Clamp Force & Effective Nut FactorExplore torque and clamp force using a selected nut factor, nominal diameter and an explicit percentage adjustment.Calculator · CalculateBrick Quantity & Mortar Materials CalculatorEstimate bricks and mortar materials using wall, joint and mix inputs.Calculator · CalculateBuilding Floor & Land Area Ratios CalculatorCalculate floor-area, open-space and usable-area ratios from entered areas.Calculator · CalculateBulk Material Tonnage & Allowance CalculatorEstimate bulk material mass and cost with a chosen extra-order percentage.Calculator · CalculateChicken Coop Area by Flock & Daytime AccessAdd floor-area allowances for standard-size and bantam chickens under three stated daytime-access assumptions.Calculator · CalculateCircular Arc Chord & Sagitta CalculatorFind the minor-arc sagitta from a circular radius and straight chord width, with an illustrated measurement guide.Calculator · CalculateCircular Pen Perimeter & Panel EquivalentsEstimate a circular pen’s perimeter from diameter and divide it by nominal panel length to obtain panel equivalents.Calculator · CalculateCircular Pipe Internal Capacity & Liquid MassCalculate the internal volume of a uniform circular pipe and the mass of a filling liquid using its density.Calculator · CalculateConcrete Column Volume & Mix CalculatorEstimate concrete for round or rectangular columns and compare material quantities.Calculator · CalculateConcrete Slab Volume & Material CalculatorEstimate concrete volume and material quantities for the selected slab form.Calculator · CalculateConcrete Volume, Density & Mass CalculatorRelate concrete volume and mass using the selected material-density preset.Calculator · CalculateCrushed Stone Volume & Fixed-Density WeightEstimate rectangular or round/oval stone volume, extra allowance and weight at a stated fixed bulk density.Calculator · CalculateCutting Speed, Spindle & Feed CalculatorRelate tool diameter, rotational speed, tooth count and feed per tooth.Calculator · CalculateDeck Board Area Allowance & Fastener BudgetEstimate boards or square profiles from deck area with the captured 10% allowance, plus area-based fastener counts and entered material cost.Calculator · CalculateDriveway Gravel Volume, Mass & Cost CalculatorEstimate gravel quantity and material spending for a uniform rectangular layer.Calculator · CalculateDrywall Area & Panel Quantity CalculatorEstimate wall and ceiling coverage, subtract openings and calculate panel quantities.Calculator · CalculateEight-Mode Area & Square-Meter ConverterCalculate area for rectangles, squares, circles, triangles and regular polygons, or convert a supplied area between units.Calculator · CalculateElliptical Arch Rise and Focal Marking PositionsElliptical Arch Rise and Focal Marking Positions. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculateFastener Shank–Head Midpoint Hole DiameterCalculate the diameter halfway between a positive fastener shank and a larger head in this geometric model.Calculator · CalculateFence Post Length Split by a Chosen Embedment RatioFence Post Length Split by a Chosen Embedment Ratio. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculateFence Posts & Spacing CalculatorEstimate fence post requirements from run length and spacing.Calculator · CalculateFence Stain Coverage, Coats & Material CostEstimate liquid stain and entered material cost for one or both fence faces, with one-coat, two-coat and box-fence assumptions.Calculator · CalculateFlooring Area & Material Cost CalculatorCalculate flooring coverage and estimate material cost with an allowance.Calculator · CalculateFlooring Area, Waste Allowance & Material CostCalculate rectangular room area, extra material for waste, and material-only cost with area and currency unit selectors.Calculator · CalculateGravel Bed Volume, Tonnage & Budget CalculatorConvert rectangular gravel-bed dimensions into material volume, tonnage and cost.Calculator · CalculateHollow Pipe Mass, Wall Thickness and Mass per LengthHollow 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.Calculator · CalculateIdeal Conical Recess Depth CalculatorFind full cone depth from top diameter and included angle.Calculator · CalculateLandscape Stone Volume & Allowance CalculatorEstimate stone volume for rectangular or circular beds with an added allowance.Calculator · CalculateLeaning Ladder Geometry and Rail Length Beyond SupportLeaning Ladder Geometry and Rail Length Beyond Support. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculateLimestone Fill, Allowance & Cost CalculatorEstimate limestone fill volume, ordering allowance, mass and material cost.Calculator · CalculateLumber Board Feet & CostCalculate lumber volume in board feet from board dimensions and count, then multiply by a supplied price per board foot.Calculator · CalculateLumber Board Feet & Cost CalculatorCalculate board-foot volume from lumber dimensions and quantity.Calculator · CalculateLumber Piece Volume & Order Cost CalculatorAdd up lumber volume, length and cost from actual piece dimensions.Calculator · CalculateMeasured Liquid Flow Rate CalculatorCalculate a liquid flow rate from collected volume and elapsed time.Calculator · CalculateMetal Roof Area & Panel Cost Lower BoundEstimate roof area from measured surface dimensions or footprint and pitch, then calculate an area-only panel-count and material-cost lower bound.Calculator · CalculateMortar Bags from Entered Brick or Block YieldRound mortar bags up from masonry count and entered coverage per bag, then calculate total dry bag mass.Calculator · CalculatePaver Bedding Sand Order CalculatorEstimate bedding sand volume, mass and material cost.Calculator · CalculatePaver Quantity & Installation Cost CalculatorEstimate pavers and project costs from the area and paver dimensions.Calculator · CalculatePea Gravel Volume, Weight & Cost CalculatorEstimate pea gravel volume, mass and cost using a chosen bulk density.Calculator · CalculatePipe Capacity & Liquid Mass CalculatorCalculate the internal capacity of a pipe and the mass of its contents.Calculator · CalculatePipe Rolling Offset, Centerline Travel and RunPipe Rolling Offset, Centerline Travel and Run. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculatePlywood Coverage, Sheets & Cost CalculatorEstimate plywood sheet quantities and cost from coverage and sheet dimensions.Calculator · CalculatePlywood Whole-Sheet Area Estimate and Material BudgetPlywood Whole-Sheet Area Estimate and Material Budget. Use retained unit selectors and documented geometric or area assumptions to calculate quantities and supported inverse relationships.Calculator · CalculatePost Hole Volume & Order CalculatorCalculate cylindrical or rectangular hole volume and an ordering allowance.Calculator · CalculatePost-Hole Concrete Volume with Three-Times Hole DimensionsPost-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.Calculator · CalculateRamp Rise, Run & Slope CalculatorCalculate ramp geometry from a selected ratio or your own rise and run.Calculator · CalculateRectangular & Oval Pool Fill CalculatorEstimate pool water volume and fill cost from average depth.Calculator · CalculateRectangular Fence Length with Optional Gate OpeningRectangular Fence Length with Optional Gate Opening. Use retained unit controls, geometric inverse relationships and explicit planning assumptions.Calculator · CalculateRectangular or Circular Coating VolumeEstimate geometric mixed-coating volume from a rectangular or circular surface and a uniform entered thickness.Calculator · CalculateRectangular Paving Pieces & Installed Cost CalculatorEstimate whole paver counts, material spending and area-based installation costs.Calculator · CalculateRectangular Rebar Grid Length & Stock Lower BoundEstimate two-direction rebar grid length from slab dimensions, edge offsets and maximum spacing, with a clearly labeled stock-length lower bound.Calculator · CalculateRectangular Solid Volume & Mass CalculatorEstimate a solid rectangular object’s volume and mass from its density.Calculator · CalculateRectangular Square-Yard Area & Cost CalculatorConvert rectangular dimensions into square yards and estimate cost from an area price.Calculator · CalculateRiver Rock Bed & Allowance Budget CalculatorEstimate decorative rock volume, mass and spending with an added allowance.Calculator · CalculateRoad Base Ordering Allowance CalculatorEstimate base-course volume, mass and cost with a chosen additional-material percentage.Calculator · CalculateRoof Pitch, Angle & Rise CalculatorConvert roof rise and run into pitch and angle, or calculate an unknown dimension.Calculator · CalculateRoof Rise, Run, Rafter & Pitch GeometryRelate rise, horizontal run, geometric rafter length, angle, percentage slope and rise per 12 units of run.Calculator · CalculateRoof Slope Area & Entered Unit CostConvert horizontal projected area into a uniform-pitch surface area and apply an entered price per area unit.Calculator · CalculateRoom Airflow Change Rate CalculatorCompare airflow volume per hour with the volume of a room.Calculator · CalculateRoom Paint Quantity & Cost CalculatorEstimate wall paint after subtracting doors and windows, with coats and coverage.Calculator · CalculateRoom Transmission Heat Loss with Fixed Opening SizesEstimate a room’s simplified transmission heat loss using wall U-value, captured window and door assumptions, and indoor/outdoor temperatures.Calculator · CalculateRoom Volume & Required Airflow CalculatorConvert a chosen air-change target into a nominal volumetric airflow.