Unit Converters
Free unit converters for weight, length, distance, temperature, and currency, instantly in your browser.
Weight Converter
Convert between kilograms, pounds, ounces, and stone.
Length Converter
Convert between centimeters, millimeters, inches, and feet.
Distance Converter
Convert between miles, kilometers, meters, and feet.
Temperature Converter
Convert between Fahrenheit, Celsius, and Kelvin.
Currency Converter
Convert between USD, EUR, GBP, and other currencies instantly.
Ring Size Calculator
Find your US and UK ring size from a diameter or circumference measurement, plus a full size chart.
Bra Size Calculator
Enter your band and bust measurements to find your bra size and cup size.
Shoe Size Converter
Convert between US, UK, and EU shoe sizes for men and women.
Volume Converter
Convert between milliliters, liters, cups, tablespoons, and more.
Speed Converter
Convert between mph, km/h, m/s, knots, and ft/s.
VIN Decoder
Decode any 17-character Vehicle Identification Number to see its model year, country of origin, and vehicle details.
Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals back to numbers, with a step-by-step breakdown.
Number to Words Converter
Convert any number into written words great for checks, invoices, and legal documents.
Height Converter
Convert height between feet and inches, centimeters, meters, and millimeters.
GPS Coordinate Converter
Convert latitude and longitude between decimal degrees and degrees-minutes-seconds format.
Choosing and using unit converters
Conversion tools help translate a value from one measurement system or notation into another. Select or enter the source unit carefully, then confirm the destination unit before copying the result. Pages include explanations and common reference points so you can tell whether the converted value is reasonable.
Tips for reliable results
Rounding matters when a result will be used for construction, medication, shipping, engineering, or another precision-sensitive job. Keep additional decimal places during intermediate calculations and round only at the end. For regulated or safety-critical work, confirm the conversion against the applicable official standard or a calibrated instrument.
Choose a tool above to see its inputs, method, privacy notes, examples, limitations, and answers to common questions. Related tools are linked on every page so you can continue a task without returning to search.