ToolBirch

Unit Converter

Convert length, mass, temperature and data units precisely.Calculators

Unit Converter

Convert between metric and imperial units for length, mass, temperature and data. Factors use exact standard definitions.

0.1 cm

1 mm = 0.1 cm

About this tool

One converter for the conversions that come up weekly: metres to feet, kilograms to pounds, Celsius to Fahrenheit, megabytes to gibibytes. Factors are the exact standard definitions, not rounded shortcuts.

How to use the Unit Converter tool

  1. Pick a category. Length, mass, temperature or data.
  2. Choose the units. Select the source and target units from the dropdowns.
  3. Enter the value. The converted result updates immediately, shown with sensible precision.

Supported formats

Input

  • A numeric value
  • Units within one category

Output

  • The converted value
  • Full-precision readout

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

Which data units are these?

Both decimal (KB, MB, GB — powers of 1000) and binary (KiB, MiB, GiB — powers of 1024), labelled clearly so you pick the right one.

How exact are the factors?

They use the standard definitions: an inch is exactly 2.54 cm, a pound exactly 453.59237 grams.

Is temperature conversion formula-based?

Yes. Fahrenheit and Kelvin convert through the exact formulas rather than a fixed factor.

Why does the result round?

Display is limited to 10 significant digits; the full floating-point value is used internally.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • No area, volume, speed or energy categories yet.
  • Results display up to 10 significant digits; no unit-specific formatting.
  • Cross-category conversion (such as mass to volume) is not possible and not attempted.

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