🎈 Pressure
Convert pressure units free: pascal, bar, PSI, atmosphere, mmHg. For tyres, weather and engineering. Instant results.
🎈 Pressure
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About the Pressure Tool
Pressure units differ by field. Tyre pressure is quoted in PSI or bar depending on where you are, weather reports use hectopascals or millibars, engineering specifications use pascals, and blood pressure uses millimetres of mercury — a unit that survives from mercury column manometers.
Converting correctly matters practically: inflating tyres to a PSI figure when the specification was in bar produces a significantly wrong result. This converter handles pascals, kilopascals, bar, PSI, atmospheres, and mmHg instantly in your browser.
How to Use Pressure
- Enter the pressure value.
- Select the source unit.
- Select the target unit.
- Read the converted result.
When to Use This Tool
- Converting tyre pressure specifications between PSI and bar
- Reading weather barometric pressure across unit conventions
- Working with engineering specifications in pascals or kPa
- Converting gas cylinder or system pressures
- Interpreting blood pressure figures in mmHg
Things Worth Knowing
- One bar is 100,000 pascals, very close to one standard atmosphere.
- Standard atmospheric pressure at sea level is 101,325 Pa, or 1013.25 hPa.
- One bar is approximately 14.5 PSI — a useful mental factor for tyres.
Quick Facts
| Tool name | Pressure |
| Category | Unit Converters |
| Price | Free — no account, no trial, no watermark |
| Where it runs | Entirely in your browser (client-side) |
| Files uploaded | None — your data never leaves your device |
| File size limit | None imposed; limited only by device memory |
| Works offline | Yes, once the page has loaded |
| Platforms | Windows, macOS, Linux, Android, iOS |
Frequently Asked Questions
How do I convert PSI to bar?
Divide by 14.504. A 32 PSI tyre pressure is about 2.2 bar. For quick estimates, dividing by 14.5 is close enough.
What is the difference between bar and atmosphere?
A bar is defined as exactly 100,000 pascals. A standard atmosphere is 101,325 pascals — about 1.3% higher. They are close enough to be used interchangeably in casual contexts but not in precise work.
Why is blood pressure measured in mmHg?
Because early sphygmomanometers used a mercury column, and the height of that column in millimetres was the direct reading. The unit persisted even after mercury instruments were replaced.
What pressure should my car tyres be?
Check the placard inside the driver’s door frame or the owner’s manual — it varies by vehicle and load. Never use the maximum pressure printed on the tyre sidewall, which is a limit rather than a recommendation.