//precision calculators
Calculate with confidence.
Practical calculators with transparent formulas, explicit assumptions and results that explain themselves.
> 66 published · sources cited
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Featured calculators
Published tools exercise distinct formula families, precision behavior and review workflows.
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Browse by task
Categories are compact editorial indexes, with availability derived from the registry.
01Electrical & ElectronicsBatteries, circuits and power.Electrical Power CalculatorCapacitor Charge CalculatorInductor Energy CalculatorElectricity Cost CalculatorSeries Resistors CalculatorParallel Resistor CalculatorBattery Runtime CalculatorOhm's Law CalculatorVoltage Divider CalculatorLED Series Resistor CalculatorCapacitor Energy CalculatorBattery Capacity CalculatorTransformer CalculatorPCB Trace Resistance CalculatorMotor Current Calculator15 published
02ConstructionMaterials, areas and volumes.Concrete Slab CalculatorConcrete Column Calculator2 published
03ManufacturingMachining, tolerances and process.Cutting Speed CalculatorTakt Time CalculatorScrap Rate CalculatorOEE CalculatorMaterial Yield CalculatorProduction Cycle Time Calculator6 published
04MathEveryday and applied mathematics.Fraction Subtraction CalculatorFraction SimplifierSignificant Figures CalculatorRounding CalculatorFraction CalculatorPercentage CalculatorLCM CalculatorGCF CalculatorModulo CalculatorPrime Factorization CalculatorHex CalculatorOctal CalculatorPrime Number CheckerFactors of a Number CalculatorDivisors CalculatorBase ConverterRoman Numeral ConverterScientific Notation CalculatorPercentage Change CalculatorCombination Calculator (nCr)Permutation Calculator (nPr)21 published
06EverydayPractical day-to-day tools.Fuel Cost CalculatorDiscount CalculatorScreen Size Calculator3 published
07Health & FitnessBody metrics, energy and training (non-clinical).BMR CalculatorTDEE CalculatorBody Fat Calculator (US Navy)Ideal Weight CalculatorMax Heart Rate CalculatorTarget Heart Rate CalculatorRunning Pace Calculator7 published
08ConvertersUnits, measures and conversions.Area ConverterCooking Measurement ConverterEnergy ConverterPower ConverterForce ConverterAngle ConverterFrequency ConverterAcceleration ConverterDensity Converter9 published
//method first
Trust comes from the work behind the result.
- 01Defined methodInputs, outputs, formulas, scope and exclusions are explicit.
- 02Independent fixturesExpected results are established separately from the implementation.
- 03Versioned sourcesSources record publisher, version, date, jurisdiction and applicability.
- 04Controlled publicationRobots, sitemap, claims and advertising derive from one publication state.