Unit Converter

Convert length, weight, volume, area, speed, and data — with two-way input and instant results.

How the Unit Converter Works

Select a category (Length, Weight, Volume, Area, Speed, or Data), then choose your source and target units from the dropdowns. Enter a value in either field — changing the top value updates the bottom, and vice versa. Click the swap button (↔) to flip the conversion direction.

All conversions are based on exact conversion factors. Results are displayed with up to 10 significant figures, using scientific notation for very large or very small values.

Frequently Asked Questions

How accurate are the conversions?
The conversions use precise SI-defined factors. For most everyday uses, results are accurate to at least 6 significant figures. Some units like the pound and mile have exact defined values (1 lb = 453.592 g exactly).
What does the Data category convert?
The Data category converts between bits, bytes, and decimal prefixes (KB = 1,000 bytes, MB = 1,000,000 bytes, etc.). Note: this uses SI decimal prefixes, not binary (1 KB = 1,000 B, not 1,024 B).
Can I convert Celsius to Fahrenheit here?
Temperature conversion requires a formula (not just a multiplication factor), so it's handled by a dedicated Temperature Converter tool. Check the related tools below.
What units are included?
Length: mm, cm, m, km, inch, foot, yard, mile. Weight: mg, g, kg, oz, lb, stone. Volume: ml, L, fl oz (US), cup, pint, gallon. Area: mm², cm², m², km², in², ft², yd², acre, hectare. Speed: m/s, km/h, mph, knots. Data: bit, byte, KB, MB, GB, TB, PB.

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