332 calculators · 14 categories

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Free online calculators for finance, health, math and more.
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Popular calculators

A useful place to start

Browse all 332

Loan / EMI CalculatorPopular

Find your monthly instalment and the full cost of a fixed-rate loan.

BMI CalculatorPopular

Calculate the ratio of body weight to height squared.

Average CalculatorPopular

Find the mean, median, range and sum of your numbers.

Area CalculatorPopular

Find the area and perimeter of a rectangle.

Compound Interest CalculatorPopular

Explore how an initial investment grows with regular compounding.

Percentage CalculatorPopular

Work out a percentage of any number.

Running Pace CalculatorPopular

Find average pace and speed for your run.

Discount CalculatorPopular

See the saving and final price after a percentage discount.

Browse by category

FinanceMathHealthConversionEveryday LifeConstructionStatisticsPhysicsChemistryBiologyFoodSportsEcologyOther

Finance Calculators

Investing, borrowing & budgeting

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Loan / EMI Calculator

Find your monthly instalment and the full cost of a fixed-rate loan.

Compound Interest Calculator

Explore how an initial investment grows with regular compounding.

Simple Interest Calculator

Calculate interest without compounding.

Math Calculators

Numbers, algebra & geometry

View all (4)

Percentage Calculator

Work out a percentage of any number.

Area Calculator

Find the area and perimeter of a rectangle.

Pythagorean Theorem Calculator

Find the hypotenuse of a right triangle.

Health Calculators

Body measurements & everyday fitness

View all (3)

BMI Calculator

Calculate the ratio of body weight to height squared.

Body Surface Area Calculator

Estimate surface area using the Mosteller equation.

Waist-to-Height Ratio Calculator

Express waist circumference as a fraction of height.

Conversion Calculators

Length, temperature & area

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Length Converter

Convert metres into common metric and imperial units.

Temperature Converter

Convert Celsius to Fahrenheit and Kelvin.

Acres to Hectares Converter

Convert land area from acres into hectares and square metres.

Everyday Life Calculators

Dates, time & daily planning

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Time Duration Calculator

Convert a duration into hours, minutes and seconds.

Tip Calculator

Split a bill and tip evenly between people.

Fuel Cost Calculator

Estimate the fuel used and cost of a journey.

Construction Calculators

Materials, spaces & project quantities

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Concrete Calculator

Estimate the volume of a rectangular concrete slab.

Tile Calculator

Estimate tile quantities from floor and tile dimensions.

Paint Calculator

Estimate paint volume for a chosen area and number of coats.

Statistics Calculators

Averages, spread & data

View all (3)

Average Calculator

Find the mean, median, range and sum of your numbers.

Standard Deviation Calculator

Measure the spread of a numeric dataset.

Probability Calculator

Convert favourable and total outcomes into a probability.

Physics Calculators

Motion, forces & electricity

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Ohm’s Law Calculator

Find current and power from voltage and resistance.

Speed Calculator

Calculate average speed from distance and elapsed time.

Kinetic Energy Calculator

Calculate the kinetic energy of a moving mass.

Chemistry Calculators

Solutions, reactions & quantities

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Molarity Calculator

Calculate molar concentration from amount and solution volume.

Dilution Calculator

Find the stock solution volume needed for a target concentration.

Percent Yield Calculator

Compare an actual reaction yield with its theoretical maximum.

Biology Calculators

Populations, growth & laboratory maths

View all (3)

Population Growth Calculator

Model exponential growth at a constant rate.

Doubling Time Calculator

Find how long constant compound growth takes to double.

Cell Concentration Calculator

Convert a counted number of cells and sampled volume into concentration.

Food Calculators

Recipes, portions & proportions

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Recipe Scaling Calculator

Adjust an ingredient amount for a different serving count.

Baker’s Percentage Calculator

Express an ingredient as a percentage of flour weight.

Unit Price Calculator

Compare food prices using cost per kilogram.

Sports Calculators

Pace, performance & training

View all (3)

Running Pace Calculator

Find average pace and speed for your run.

One Rep Max Calculator

Estimate a one-repetition maximum with the Epley equation.

Winning Percentage Calculator

Calculate the share of games won.

Ecology Calculators

Energy, water & resource use

View all (3)

Energy Use Calculator

Estimate electricity consumption and cost.

Water Use Calculator

Estimate water consumption from flow rate and usage time.

Electricity Emissions Calculator

Estimate emissions using your chosen electricity emissions factor.

Other Calculators

Web metrics & general utilities

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Bounce Rate Calculator

Calculate a simple single-page-session percentage.

Download Time Calculator

Estimate transfer time from file size and connection speed.

Conversion Rate Calculator

Measure the share of visitors who complete a desired action.

Make sense of the numbers

Choose a calculator, enter your values and watch the answer update. Every tool includes its formula and a worked example so you can follow the method. Category pages bring related tools together, from household budgeting to classroom mathematics.

Inputs are processed locally. Assumptions and limits are shown alongside each calculation.