Pressure Converter
Convert between PSI, bar, kPa, atm, and mmHg — then check the value against what things are normally inflated to.
| Unit | Value | What it is | |
|---|---|---|---|
| PSIsource | 32 | Pounds per square inch — tyres, US/UK gauges | |
| bar | 2.206 | Metric, ~1 atmosphere — European gauges | |
| kPa | 220.63 | Kilopascal — the SI unit, used in AU/NZ | |
| atm | 2.177 | Standard atmosphere — sea-level air pressure | |
| mmHg | 1654.9 | Millimetres of mercury — medical, barometric |
Common pressures
Shown in PSI — change the “From” unit above to switch. “Use” loads a value into the converter.
Vehicle tyres
| Item | Typical (PSI) | Notes | |
|---|---|---|---|
| Car tyre (passenger) | 30–35 | Check the door-jamb placard — the number on the tyre wall is the maximum, not the target. | |
| Car tyre (compact spare) | 60 | Space-saver spares run far higher than normal tyres. | |
| SUV / light truck tyre | 35–45 | Higher when loaded or towing. | |
| Lorry / truck tyre | 100–120 | Commercial vehicles, load-dependent. | |
| Motorcycle tyre | 28–42 | Front is usually a few psi lower than rear. |
Bicycle tyres
| Item | Typical (PSI) | Notes | |
|---|---|---|---|
| Road bike (23–25mm) | 80–130 | Narrow, high-pressure. Lower end for heavier riders on rough roads. | |
| Road bike (28–32mm) | 60–80 | Wider modern road tyres run notably softer. | |
| Gravel bike | 35–50 | Tubeless setups sit at the low end for grip. | |
| Hybrid / commuter | 50–70 | General-purpose 35–42mm tyres. | |
| Mountain bike | 22–35 | Lower for loose terrain, higher for hardpack. | |
| Fat bike | 5–15 | Snow and sand — very low pressure for float. | |
| Kids' bike | 30–50 | Check the tyre sidewall range. |
Sports balls
| Item | Typical (PSI) | Notes | |
|---|---|---|---|
| Football (soccer) | 8.7–16 | FIFA spec: 0.6–1.1 atm at sea level. | |
| Basketball | 7.5–8.5 | NBA spec. Should bounce to ~49–54in when dropped from 6ft. | |
| Volleyball | 4.3–4.6 | FIVB spec — the softest of the common balls. | |
| Water polo ball | 13–14 | Men's 90–97 kPa; women's slightly lower. | |
| American football | 12.5–13.5 | The NFL range at the centre of "Deflategate". | |
| Rugby ball | 9.5–10 | World Rugby spec: 65.7–68.8 kPa. | |
| Netball | 8–9 | Similar to a basketball. | |
| Tennis ball | 12–14 | Pressurised internally; balls go dead as this leaks away. |
For scale
| Item | Typical (PSI) | Notes | |
|---|---|---|---|
| Atmosphere at sea level | 14.7 | Absolute, not gauge — this is the zero point every gauge reads from. | |
| Mains water supply | 40–80 | Typical household range. | |
| Espresso machine | 130–135 | The classic 9 bar at the group head. | |
| Car tyre blowout risk | 50 | Well beyond a passenger tyre's normal range. |
Reference
1 bar = 14.5038 psi = 100 kPa ≈ 0.9869 atm
1 atm = 14.6959 psi = 101.325 kPa = 760 mmHg
Every value above is gauge pressure — what a pump reads, i.e. above atmospheric. Absolute pressure = gauge + 14.7 psi.
Tyre pressures are cold values. A tyre warms as you drive and can read several psi higher.
Instructions
Converts a pressure between PSI, bar, kPa, atm and mmHg, and shows what things are normally inflated to.
- Type the number into Value and pick what unit it is in under From.
- Every other unit is filled in immediately — copy whichever one you need.
- Scroll to Common pressures to sanity-check the number, and press Use on any row to load it into the converter.
Tips
- The reference tables are shown in your chosen From unit, so switching to bar re-labels every typical value in bar.
- Everything here is gauge pressure — what a pump reads, i.e. above atmospheric. Absolute pressure = gauge + 14.7 psi.
- Tyre figures are cold values; a tyre warms as you drive and reads several psi higher.
- Hit Example, then click the value field for a car tyre quoted in bar, or any Use button to pull that reading in.