Your one-stop hub for online calculators & tools

From loan payments and BMI to unit conversions — get accurate results in seconds, 100% free.

Why CalcTools?

Powerful, Accurate & Free

Everything you need for quick, reliable calculations in your browser.

Lightning-fast calculations as you type.

All tools are free with zero registration.

Optimised for any device, anywhere.

Formulas & rates updated regularly.

Keyboard & screen-reader friendly design.

Community-driven with transparent code.

Jump right in — more tools are added every week.

Calculate monthly repayments, interest & schedules.

Find your Body Mass Index & health range.

Convert length, weight, temperature & more.

Work out percentage increases, decreases & differences.

Calculate exact age from date of birth.

Find the duration between two dates.

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