Convert length, weight, temperature, speed, and area between metric and imperial units.
Free online unit converters for length, weight, temperature, speed, area, volume, data storage, time, pressure, and more. Also includes specialized converters: shoe size converter (US, UK, EU, CM), bra size calculator, ring size calculator, online ruler (pixel/cm/inches), coordinate converter (GPS DD/DMS/DDM/UTM), world clock, timezone converter, and Roman numeral converter. All conversions use standard formulas and reference tables.
Convert numbers to English words. Supports trillions, decimals, negatives, and check-writing format.
Convert length between metric and imperial units. Meters, feet, inches, kilometers, miles, and more.
Convert weight between metric and imperial units. Kilograms, pounds, ounces, stones, and more.
Convert between Celsius, Fahrenheit, Kelvin, and Rankine. See conversion formulas for each.
Convert speed units: km/h, mph, m/s, knots, and ft/s. Real-time conversion for any speed.
Convert area units: square meters, square feet, acres, hectares, square miles, and more.
Convert times between world timezones. Compare UTC, EST, PST, GMT, CET, IST, JST, and more.
Convert volume units: liters, gallons, cups, milliliters, pints, quarts, and fluid ounces.
Convert digital storage units: bytes, KB, MB, GB, TB, PB. Binary (1024) based conversion.
Convert time units: seconds, minutes, hours, days, weeks, months, and years.
Convert pressure units: Pascal, bar, psi, atm, mmHg, and torr.
Convert numbers to Roman numerals and back. Supports values from 1 to 3,999 with instant bidirectional conversion.
Convert between 30+ currencies with live exchange rates. Auto-updates every 10 minutes. No API key required.
Convert shoe sizes between US, UK, EU, and CM for men, women, and kids. International sizing with full chart.
Convert GPS coordinates between Decimal Degrees, DMS, DDM, and view UTM zone information.
Ideal for cooking and baking measurements, DIY and construction projects, travel and navigation, online shopping for international sizes, scientific calculations, fitness tracking, and clothing size conversions.
All conversions use internationally standardized conversion factors. Length, weight, and temperature converters use NIST-tested formulas. Currency converter uses live exchange rates updated every 10 minutes.
Yes. Every unit converter supports both metric (SI) and imperial/US customary units, with full cross-conversion between systems. Results include all supported units for easy comparison.
Stand on a piece of paper, trace your foot, measure from heel to longest toe in centimeters, and use our shoe size converter. We support US, UK, EU, and CM sizing for men, women, and kids.
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