Pick a category, enter a value, choose the units — get an accurate SI-based conversion.
Open the free converter →Not a generic converter — this one covers the quantities you actually work with, with the units you actually use: bar, psi, kPa, kg/cm², mmHg for pressure; m³/h, US/UK gpm, L/s, bbl/day for flow; cP, Pa·s, poise for viscosity; and correct handling of the °C / °F / K / °R temperature offsets.
| Category | Handy conversion |
|---|---|
| Pressure | 1 bar = 100 kPa · 1 atm = 14.696 psi · 1 psi = 6.8948 kPa |
| Flow | 1 US gpm = 0.2271 m³/h · 1 m³/h = 0.2778 L/s |
| Temperature | 100 °C = 212 °F · 0 °C = 273.15 K |
| Viscosity | 1 cP = 0.001 Pa·s = 1 mPa·s |
| Volume | 1 US gal = 3.7854 L · 1 bbl = 158.99 L |
| Power | 1 hp = 0.7457 kW |
Each category has a base SI unit; a value is converted to the base unit and then to the target unit using exact, SI-defined factors. Temperature uses the correct additive offsets rather than a simple ratio, so °C ↔ °F ↔ K ↔ °R are always right.
Pressure, flow, temperature, length, volume, mass, power, density, viscosity and energy.
Multiply by 6.894757 — e.g. 50 psi = 344.7 kPa.
Yes — completely free.
Related: Reynolds number · Tank volume · Line sizing