Unit Converter

Convert length, weight, temperature, area, volume, speed, and data units.

Quick answer: Free online Unit Converter. Convert length, weight, temperature, speed, area, volume, and data sizes instantly with exact international definitions.

Millimeters → Centimeters0.1

exact international definitions — computed locally

One converter for every common measurement: pick a category, choose your units, and the conversion updates as you type — using exact international definitions.

How it works

  1. Select the category of measurement you want to convert (e.g., Length or Weight).
  2. Choose your starting unit and your target unit.
  3. Enter the value, and the engine calculates the exact conversion instantly.

Frequently asked questions

Are the factors exact?

Yes — they are the international (SI) definitions, not approximations: the inch is defined as exactly 25.4 mm.

US vs UK gallons?

Different units: 1 US gal = 3.785 L, 1 UK gal = 4.546 L. The volume converter lists both.

KB vs KiB?

Decimal (1000-based) vs binary (1024-based). Storage marketing uses decimal; operating systems often report binary.

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