Unit Converter

Free Online Unit Converter

Convert between common units of measurement instantly. Supports length, weight, temperature, area, volume, speed, and time. All calculations happen in your browser — fast, private, and works offline.

Supported Categories

• Length — millimeter, centimeter, meter, kilometer, inch, foot, yard, mile, nautical mile
• Weight — milligram, gram, kilogram, metric ton, ounce, pound, stone
• Temperature — Celsius, Fahrenheit, Kelvin
• Area — mm², cm², m², km², in², ft², acre, hectare
• Volume — ml, liter, m³, teaspoon, tablespoon, cup, pint, quart, gallon
• Speed — m/s, km/h, mph, knots, ft/s
• Time — millisecond, second, minute, hour, day, week, month, year

Frequently Asked Questions

How accurate are the conversions?

Conversions use standard conversion factors and are accurate to JavaScript's floating-point precision (approximately 15 significant digits).

Why do you show all conversions at once?

The "all conversions" grid below the converter shows your input value in every unit of the selected category, making it easy to compare.