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Pressure converter
Force per unit area, for tyres, weather and engineering. 8 units, converted from one table of exact factors.
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1 psi in every other pressure unit
Computed by the same engine that runs the converter above, so these can never drift apart from it.
| From | Equals | Unit |
|---|---|---|
| 1 psi | 6,894.7573 | pascal (Pa) |
| 1 psi | 6.8947573 | kilopascal (kPa) |
| 1 psi | 0.068947573 | bar (bar) |
| 1 psi | 0.068045964 | atmosphere (atm) |
| 1 psi | 51.714933 | torr (Torr) |
| 1 psi | 51.714925 | millimeter of mercury (mmHg) |
| 1 psi | 2.0360205 | inch of mercury (inHg) |
What each unit actually is
Most converters give you a number and stop. Where a figure is exact by definition we say so, and where it is an average or shifts with conditions we say that too — that is usually the thing you needed to know.
| Unit | Symbol | What it actually is |
|---|---|---|
| pascal | Pa | One newton per square metre. The SI derived unit. |
| kilopascal | kPa | Exact. The unit most tyre placards use outside the US. |
| bar | bar | Exactly 100,000 Pa. Close to, but not the same as, one atmosphere. |
| psi | psi | Pounds per square inch. Exact, since the pound and inch are defined. |
| atmosphere | atm | Exactly 101,325 Pa by definition. Standard sea-level pressure. |
| torr | Torr | Exactly 1/760 of an atmosphere. |
| millimeter of mercury | mmHg | Very slightly different from the torr. Still the unit of blood pressure. |
| inch of mercury | inHg | Used in American aviation and weather reporting. |