About UnitSwapper

UnitSwapper is a free, fast, and accurate unit conversion tool built for everyday use. Whether you need to convert length, weight, temperature, area, volume, speed, data, or time - we have you covered.

Our conversions happen instantly in your browser with no server round-trips. We support over 80 units across 8 categories, with precise conversion factors sourced from international standards.

For developers, a free REST API exposes the same conversion engine: categories, units, and conversions, all as simple JSON endpoints.

UnitSwapper is designed to be simple, reliable, and accessible. No sign-up required, no ads blocking your view - just the conversion you need, right when you need it.