Convert pressure between Pa, bar, atm, psi, mmHg and more.
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How do you convert pressure between Pa, bar, atm and psi?
Each unit converts through pascals: 1 atm = 101,325 Pa, 1 bar = 100,000 Pa, and 1 psi ≈ 6,894.76 Pa. Multiply by the source factor to reach pascals, then divide by the target factor. For example, 1 atm equals 101,325 Pa, about 14.696 psi. mmHg and torr are essentially identical for everyday use.
Understanding your result
mmHg and torr are essentially identical for everyday use.
Formula and method
Each unit converts through pascals (1 atm = 101,325 Pa; 1 bar = 100,000 Pa; 1 psi ≈ 6,894.76 Pa).
Assumptions and limitations
Conversions are exact ratios (1 atm = 101,325 Pa, 1 psi = 6,894.76 Pa). The tool converts absolute pressure; it does not distinguish gauge pressure — measured relative to the atmosphere, as on a tyre gauge (psig) — from absolute pressure, so add or subtract one atmosphere yourself when a reading is quoted as gauge.
Worked example
1 atm equals 101,325 Pa, about 14.696 psi.
Common pressure conversions
| Convert | Equals |
|---|---|
| 1 atmosphere | 101,325 pascals |
| 1 atmosphere | 14.6959 psi |
| 1 bar | 14.5038 psi |
| 1 psi | 6.89476 kilopascals |
| 1 atmosphere | 1.01325 bar |
| 1 atmosphere | 760 mmHg |
| 1 bar | 100 kilopascals |
| 1 mmHg | 133.322 pascals |
How to use this tool
- Enter a value and choose units.
- The converted value appears instantly.
Common mistakes to avoid
- Confusing gauge pressure with absolute pressure.
About the Pressure Converter
Convert a pressure value between pascals, bar, atmospheres, psi and millimetres of mercury.
Who should use this tool
Drivers checking tyre pressure in psi or bar, divers and weather watchers working in atmospheres or millibars, engineers using pascals and kilopascals, and anyone reading a blood-pressure figure in mmHg. It covers pascals, kilopascals, bar, atmospheres, psi and millimetres of mercury.
Benefits
- Covers automotive (psi, bar), scientific (Pa, kPa), weather (atm) and medical (mmHg) units
- Exact standard factors for consistent, comparable figures
- Handles the wide range from pascals to atmospheres
- Runs offline with no sign-up
Practical use cases
- Converting a tyre-pressure spec between psi and bar
- Reading a weather pressure in atmospheres, bar or hectopascals
- Working engineering problems in pascals and kilopascals
- Interpreting a blood-pressure reading quoted in mmHg
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Frequently asked questions
How many psi in a bar?
One bar is about 14.504 psi.
How many psi are in one bar?
One bar equals 14.5038 psi, and one atmosphere (101,325 Pa) is 14.6959 psi. Car tyres are often inflated to around 2.2 to 2.5 bar, which is roughly 32 to 36 psi.
What is standard atmospheric pressure?
Standard atmospheric pressure is 101,325 pascals — equal to 1 atmosphere, 1.01325 bar, 14.6959 psi, or 760 mmHg. Everyday weather pressure stays close to this value.