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Calculators: 47

All calculators

Browse all 47 Calctera calculators for math, finance, dates, health, construction, conversions and more. Free tools with formulas and worked examples.

Percentage calculator

Find a percentage, a share or a relative change.

Discount calculator

See the new price and how much you save.

Proportion calculator

Find the missing value in A / B = C / X.

Loan calculator

Estimate your monthly payment and total interest.

Compound interest

Grow a starting balance with monthly contributions.

Shape area calculator

Calculate the area of a rectangle, triangle or circle.

Time calculator

Add or subtract two durations in hours and minutes.

Unit conversion

Length converter

Convert metres, kilometres, inches, feet and other length units.

Unit conversion

Mass converter

Convert grams, kilograms, tonnes, pounds and ounces.

Unit conversion

Temperature converter

Convert Celsius, Fahrenheit and kelvin.

Add or subtract dates

Move a date forward or backward by years, months, weeks and days.

Age calculator

Find age on a chosen date in years, months and days.

Unit conversion

Area converter

Convert square metres and feet, hectares, acres and other area units.

Average calculator

Find the arithmetic mean, minimum and maximum of a list.

Basic calculator

Arithmetic expressions with parentheses and decimal numbers.

BMI calculator

Calculate body mass index from height and weight for adults aged 18+.

BMR calculator

Estimate resting energy expenditure with the Mifflin–St Jeor equation.

Business days

Count working days with custom weekends and excluded dates.

Concrete calculator

Calculate rectangular concrete volume with an allowance.

Unit conversion

Cooking unit converter

Convert teaspoons, tablespoons, cups, fluid ounces and millilitres.

Currency converter

Convert currencies using a dated reference exchange rate.

Unit conversion

Data storage converter

Convert bytes, decimal KB–TB and binary KiB–TiB.

Date difference

Count days between dates and see the calendar duration.

Time duration

Find the duration between two local date-times in hours and minutes.

Flooring calculator

Estimate material area with allowance and the number of packs.

Fraction calculator

Add, subtract, multiply, divide and simplify fractions.

Fuel cost calculator

Estimate trip cost from distance, fuel consumption and fuel price.

Unit conversion

Fuel economy converter

Convert L/100 km, km/L, US MPG and imperial MPG.

GPA calculator

Calculate a credit-weighted GPA using numeric, letter or custom scales.

Grade calculator

Find a final percentage from assignment scores and weights.

Mortgage payment

Estimate monthly principal-and-interest payments and total interest.

Paint calculator

Estimate litres of paint from area, coverage and coat count.

Percentage change

Calculate the percentage increase or decrease between two values.

Ratio calculator

Simplify the ratio of two integers or decimals.

Return on investment (ROI)

Compare total proceeds with the amount invested and costs.

VAT / sales tax

Add tax to a net price or remove tax already included in a gross price.

Savings goal

Find the monthly contribution needed to reach a savings target.

Scientific calculator

Powers, roots, logarithms and trigonometry in degrees or radians.

Simple interest

Calculate interest without compounding and the final balance.

Unit conversion

Speed converter

Convert kilometres and miles per hour, metres per second and knots.

TDEE calculator

Estimate daily energy expenditure including activity.

Tile calculator

Estimate tiles and whole packs including cutting allowance.

Time zone converter

Convert date-times between time zones with daylight-saving rules.

Tip calculator

Calculate the tip, total bill and equal share per person.

Unit conversion

Volume converter

Convert litres, millilitres, cubic metres and gallons.

Weighted average

Enter values and their weights in separate rows.

Work hours / time card

Calculate shift length minus unpaid breaks.