Unit Conversion Calculators

Free unit conversion calculators for length, weight, temperature, volume, and more. Convert between metric and imperial units instantly.

14 free unit conversion calculators available.

Why Unit Conversion Calculators Matter

Unit conversion mistakes cause billion-dollar spacecraft failures, hospital medication errors, and kitchen disasters. ConvertMart's conversion tools use the exact conversion factors published by NIST and the BIPM (International Bureau of Weights and Measures), not rounded approximations, so calculations stay accurate even across multiple chained conversions. Every converter supports metric and imperial units, shows the conversion factor explicitly, and updates currency rates daily for exchange-rate-sensitive calculations.

Top Use Cases

How to Use ConvertMart's Unit Conversion Calculators

Enter a value and select the source unit. The converter shows equivalents in every common target unit at once, so you donʼt have to run multiple calculations. Conversion factors are visible beneath each result — e.g., 1 kg = 2.20462 lb — so you can verify independently. Currency conversions use exchange rates refreshed every 15 minutes from the ECB (European Central Bank) reference rates.

Popular Questions

Frequently Asked Questions

Are currency rates live?
Currency exchange rates refresh every 15 minutes from the ECB reference rates, which is the same source most banks use for nightly settlement. Rates displayed are mid-market rates, not the rates your bank will actually quote you for a retail exchange — expect a 1-3% spread on actual transactions.
Why do MB/GB conversions sometimes give different answers elsewhere?
Two conflicting conventions exist: the SI decimal standard (1 GB = 1,000 MB = 1,000,000,000 bytes) and the binary standard (1 GiB = 1,024 MiB = 1,073,741,824 bytes). Storage manufacturers use decimal; operating systems usually use binary. Our converter lets you choose which convention to apply.

All Unit Conversion Calculators (14)

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