MMaster Tools
CalculatorsRuns on your device

Unit Converter

Convert values between length, weight, temperature, volume, area, speed, and data units — swap direction with one click.

How it works

  1. 1

    Pick what you are measuring — length, weight, temperature and more.

  2. 2

    Choose the units to convert from and to, then type a value.

  3. 3

    The answer updates as you type; nothing is sent anywhere.

Questions

Why does changing the measurement reset the units?

Each measurement has its own units, so the from and to lists are rebuilt whenever you switch — kilometres make no sense once you are converting temperature.

Is temperature converted differently?

Yes. Temperature scales have an offset as well as a scale, so 0 °C is 32 °F rather than 0 °F. This tool uses the correct formula rather than multiplying by a ratio.

What is the difference between MB and MiB?

A megabyte is 1,000,000 bytes and a mebibyte is 1,048,576. Both are offered so you can match whichever convention your software uses.

Does anything leave my device?

No. The conversion is arithmetic done in your browser; nothing is uploaded or recorded.

Loan Calculator

Loan Calculator

Work out the monthly repayment, total cost, and total interest on a loan or mortgage.

Percentage Calculator

Percentage Calculator

Solve four types of percentage question — find a percentage, express one number as a percent of another, or calculate a percentage change.

Tip Calculator

Tip Calculator

Split a restaurant bill with tip, see what each person owes, and optionally round up to a clean number.

BMI Calculator

BMI Calculator

Calculate your Body Mass Index from height and weight in metric or imperial units, and see the healthy weight range for your height.

Age Calculator

Age Calculator

Find out exactly how old someone is in years, months, and days — updated to any reference date you choose.

Date Difference

Date Difference

Calculate the span between two dates: total days, weeks, business days, and a full years–months–days breakdown.