PSI to Bar converter for bike tyres
Convert tyre pressure between psi, bar and kPa. Type in either field — the other one updates as you type.
87 psi = 6.00 bar = 87.0 psi = 600 kPa
PSI to bar conversion table
| psi | bar | kPa |
|---|---|---|
| 20 | 1.38 | 138 |
| 30 | 2.07 | 207 |
| 40 | 2.76 | 276 |
| 50 | 3.45 | 345 |
| 60 | 4.14 | 414 |
| 70 | 4.83 | 483 |
| 80 | 5.52 | 552 |
| 90 | 6.21 | 621 |
| 100 | 6.89 | 689 |
| 110 | 7.58 | 758 |
| 120 | 8.27 | 827 |
Recommended tyre pressure by tyre width
A starting point only. Heavier riders go up, rough surfaces and tubeless setups go down, and the maximum printed on the sidewall always wins.
| Tyre | bar | psi |
|---|---|---|
| Road 23–25 mm | 6.0 – 7.5 | 87 – 109 |
| Road 28–30 mm | 5.0 – 6.5 | 73 – 94 |
| Gravel 32–40 mm | 2.5 – 4.0 | 36 – 58 |
| Gravel 45–50 mm | 2.0 – 3.0 | 29 – 44 |
| MTB 2.2–2.4 in | 1.5 – 2.0 | 22 – 29 |
| MTB plus / fat | 0.7 – 1.2 | 10 – 17 |
The formula
1 bar = 14.5038 psi = 100 kPa. So bar = psi ÷ 14.5038 and psi = bar × 14.5038. Pump gauges are rarely accurate to better than ±0.2 bar, so there is no point chasing the second decimal.
Frequently asked questions
- How do you convert psi to bar?
- Divide the psi value by 14.5038. For example 100 psi ÷ 14.5038 = 6.89 bar. To go the other way, multiply bar by 14.5038: 6 bar × 14.5038 = 87.0 psi.
- What tyre pressure should I run?
- It depends on tyre width, rim, surface and rider weight. As a rough guide: 25 mm road tyres run about 5.5–7 bar (80–100 psi), 32–40 mm gravel tyres about 2.5–4 bar (35–58 psi), and 2.2–2.4 inch mountain bike tyres about 1.5–2 bar (22–30 psi). Never exceed the maximum pressure printed on the tyre sidewall.
- Is bar the same as atmosphere?
- Almost. One bar is 100 kPa, and one standard atmosphere is 101.325 kPa. The difference is about 1.3 %, so pumps that print 'atm' and pumps that print 'bar' are interchangeable in practice for tyre pressure.
- Why do European pumps show bar and American pumps show psi?
- Bar is the metric unit used across Europe, and psi (pounds per square inch) is the imperial unit used in the United States and the United Kingdom. Many pumps print both scales on the same gauge.
- Does tyre pressure change my bike fit?
- Not the joint angles, but it changes comfort a lot. If you get numb hands or a sore lower back, over-inflated tyres are worth checking before you move the saddle. Pedalyze measures your riding position from a photo if you want the fit side checked too.
Related guides
- How to take bike fit photos — The photo is the measurement: camera height, 90° side-on framing, crank at 6 and 3 o'clock, clothing and lighting — everything that makes fit angles accurate.
Other tools
- Bike frame size calculator — Get your frame size from your height and cycling inseam, for road, gravel, mountain and hybrid bikes, with a size chart for each.
- Saddle height calculator — Estimate your saddle height from inseam with the LeMond method, measured from the bottom bracket to the top of the saddle.
Check this with a photo
Tyre pressure is the easy fix. Your riding position is the one that hurts. Pedalyze checks your knee, hip and back angles from two photos.