Calculators & Converters

Quick, dependable calculators and converters for percentages, units, dates and health. Each runs locally and links to focused pages for the most common conversions.

• Percentage Calculator

  Calculate percentages three ways: what is X% of Y, X is what percent of Y, and percentage change. Instant, and runs entirely in your browser.

  Open Percentage Calculator → Guide

• Age Calculator

  Work out your exact age in years, months and days — plus totals and your next birthday. Runs entirely in your browser; nothing is uploaded.

  Open Age Calculator → Guide

• BMI Calculator

  Calculate your Body Mass Index (BMI) in metric or imperial units, see your category and a healthy weight range for your height. Runs in your browser.

  Open BMI Calculator → Guide

• Unit Converter

  Convert length, weight, temperature and volume — metres to feet, kg to lb, °C to °F, cups to ml and more. Instant, and runs in your browser.

  Open Unit Converter → Guide

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