Calculator
Calculator Tools
Free calculator tools for everyday math, finance, dates, and planning.
Showing 24 of 38 tools.
ROI Calculator
Calculate ROI, net profit, return multiple, and annualized return (CAGR).
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CalculatorBMI Calculator
BMI in kg/cm or lb/ft+in with category, healthy weight range, and BMI prime.
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CalculatorLoan Calculator
Monthly payment, total interest, payoff time, and amortization schedule.
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CalculatorConcrete Calculator
Concrete volume for slabs, columns, post holes, and stairs with bag counts and cost.
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CalculatorDebt Payoff Calculator
Snowball or avalanche payoff with side-by-side comparison and monthly schedule.
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CalculatorFuel Economy Calculator
MPG, L/100km, km/L, and cost per mile from distance and fuel, with optional trip-cost projection.
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CalculatorHeart Rate Zone Calculator
Five training zones from your max HR with Tanaka, Fox, or custom formulas.
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CalculatorInflation Calculator
Adjust any amount for inflation using US CPI data or a custom rate.
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CalculatorLat Long Distance Calculator
Distance, initial bearing, and midpoint between two lat/long pairs.
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CalculatorPay Raise Calculator
Percent or amount raise on any pay rate, with hourly to annual breakdown and inflation-adjusted real raise.
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CalculatorPregnancy Due Date Calculator
Estimate due date and trimester milestones from LMP, conception, or ultrasound.
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CalculatorSquare Footage Calculator
Multi-room square footage with shapes, units, waste percentage, and cost.
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CalculatorStandard Deviation Calculator
Sample and population SD, variance, quartiles, outliers, and step by step working.
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CalculatorBreak-Even Point Calculator
Break-even units, break-even revenue, target profit, forecast profit, and sensitivity table.
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CalculatorDPI Calculator
Solve for DPI, pixels, or print size and see the print quality grade.
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CalculatorElectricity Cost Calculator
Cost per hour, day, week, month, and year for any appliance you enter.
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CalculatorFraction Calculator
Add, subtract, multiply, and divide fractions with simplified results and step-by-step working.
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CalculatorPermutation and Combination Calculator
nPr, nCr, factorial, n^r, and multiset coefficient with exact step-by-step working.
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CalculatorPrime Number Calculator
Primality test plus prime factorization, divisors, divisor count, divisor sum, and next or previous prime.
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CalculatorRight Triangle Calculator
Solve any right triangle and see sides, angles, area, perimeter, and trig values with shown steps.
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CalculatorUnit Price Calculator
Compare cost per unit across sizes and packs to spot the best value.
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CalculatorBody Fat Calculator
Body fat percentage from neck, waist, hip, and height with category and lean mass.
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CalculatorCompound Interest Calculator
Future value, time to goal, and required contribution with annual schedule.
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CalculatorDiscount Calculator
Sale price from stacked percent and amount off discounts, with optional tax and reverse mode.
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