About Simple Converter

Simple Converter is a free set of unit conversion calculators covering length, weight, temperature, and volume. No sign-up, no ads chasing you around the page — type a value, read the answer.

Where the numbers come from

Every conversion factor on this site is taken from the defining standard for the unit, not from other conversion sites:

• Imperial and US customary lengths and weights use the exact values fixed by the International Yard and Pound Agreement of 1959 (1 yard = 0.9144 m, 1 pound = 0.45359237 kg — exactly).
• Metric units follow the BIPM SI Brochure, the authoritative definition of the International System of Units.
• Temperature scales use the exact SI relations (0 °C = 273.15 K; °F = °C × 9/5 + 32).
• US volume units derive from the legal definition of the US gallon as exactly 231 cubic inches.

Each converter page cites the source for its factor, and an automated test suite checks every value against those definitions on every build.

Accuracy

Because the factors are exact by definition, results are limited only by floating-point display precision. Calculators and reference tables show six significant digits.