1
Unit Conversions
Pressure Converter — PSI, Bar, kPa, atm, mmHg & More
Move between psi, bar and metric pressure units the way gauges and spec sheets read them
Pressure is one of those measurements where the United States and the rest of the world rarely use the same number. Your tire gauge reads psi, a European car manual lists tire pressure in bar, a scuba tank is marked in bar or atm, a weather report quotes barometric pressure in inches of mercury (inHg) here but hectopascals/millibars abroad, and a blood-pressure cuff or vacuum spec talks in mmHg (torr). This converter moves any value between the eight pressure units you actually run into — pascal (Pa), kilopascal (kPa), bar, pound-force per square inch (psi), atmosphere (atm), millimeter of mercury / torr (mmHg), inch of mercury (inHg) and kilogram-force per square centimeter (kg/cm²).
The method is simple and exact: every unit is first converted to a single base — the pascal, the SI unit of pressure (1 Pa = 1 newton per square meter) — and then back out to the target unit.
The factors (pascals per unit):
- Pa = 1
- kPa = 1,000
- bar = 100,000 (a bar is defined as exactly 100 kPa)
- psi = 6,894.757293
- atm = 101,325 (the standard atmosphere, defined exactly)
- mmHg / torr = 133.322387415
- inHg = 3,386.389
- kg/cm² = 98,066.5
Formula: pascals = value × (factor of the FROM unit), then result = pascals ÷ (factor of the TO unit).
The headline conversion — psi to bar. 1 bar = 100,000 Pa and 1 psi = 6,894.757293 Pa, so 1 psi = 0.0689476 bar and 1 bar = 14.50377 psi. That's why a tire spec of 2.2 bar means roughly 32 psi (2.2 × 14.50377 = 31.9), and a US 35 psi recommendation is about 2.41 bar. Keep those two anchors in mind and most tire, bike and HVAC conversions fall out instantly.
Worked example — convert 32 psi to bar. First to pascals: 32 × 6,894.757293 = 220,632.23 Pa. Then pascals to bar: 220,632.23 ÷ 100,000 = 2.2063 bar. The common mistake is reaching for the rounded "1 bar ≈ 14.5 psi" or "1 atm ≈ 1 bar" — close, but a standard atmosphere is actually 1.01325 bar (101.325 kPa), not 1.00, and that 1.3% gap matters in lab, dive and engineering work. This tool uses the exact standard factors, so your answer matches the official ones. Pick a value, a from unit and a to unit, and you'll also get a quick table showing the same pressure in every common unit at once.
Calculator
Fill in the fields and click "Calculate" for instant results.
📰 Formula
• Convert to pascals: pascals = value × (factor of the FROM unit) • Convert out: result = pascals ÷ (factor of the TO unit) • Pa = 1 Pa • kPa = 1000 Pa • bar = 100000 Pa • psi = 6894.757293 Pa • atm = 101325 Pa • mmHg (torr) = 133.322387415 Pa • inHg = 3386.389 Pa • kg/cm² = 98066.5 Pa
📰 Formula
• Convert to pascals: pascals = value × (factor of the FROM unit) • Convert out: result = pascals ÷ (factor of the TO unit) • Pa = 1 Pa • kPa = 1000 Pa • bar = 100000 Pa • psi = 6894.757293 Pa • atm = 101325 Pa • mmHg (torr) = 133.322387415 Pa • inHg = 3386.389 Pa • kg/cm² = 98066.5 Pa
🧪 Worked examples
2
Example 2
3
Example 3
4
Example 4
⚠️ Common mistakes
- Treating 1 atm as exactly 1 bar — a standard atmosphere is 1.01325 bar (101.325 kPa), about 1.3% higher.
- Using the rounded 14.5 psi per bar instead of the exact 14.50377, which adds up on high-pressure systems.
- Confusing mmHg (torr) with inHg — 1 inHg equals 25.4 mmHg, a 25× difference if swapped.
- Reporting gauge pressure where absolute pressure is required (or vice versa) — the units are the same but the zero point differs by 1 atm.
💡 Tips
- Memorize the two anchors: 1 bar = 14.50377 psi and 1 atm = 14.6959 psi (101.325 kPa).
- Convert through the pascal as a single base; it removes guesswork between any two pressure units.
- For a quick tire gut check, multiply bar by about 14.5 to get psi, or divide psi by 14.5 to get bar.
- 1 atm ≈ 760 mmHg ≈ 29.92 inHg — handy for reading weather and altimeter pressure.
Embed this calculator on your site
Copy the code below and paste it into the HTML of your site or blog.
<iframe src="https://www.calcnimbus.com/embed/pressure-converter" width="100%" height="500" frameborder="0" style="border:1px solid #eee;border-radius:12px"></iframe>
❓ Frequently asked questions
How do I convert psi to bar?
Divide psi by 14.50377, or multiply by 0.0689476. Example: 32 psi ÷ 14.50377 = 2.2063 bar. Both come from 1 psi = 6,894.757293 Pa and 1 bar = 100,000 Pa.
How many psi are in 1 bar?
Exactly 14.50377 psi. So a tire spec of 2.2 bar is about 31.9 psi, and 3 bar is about 43.5 psi. To go back, divide psi by 14.50377.
Is 1 atmosphere the same as 1 bar?
No, they're close but not equal. A standard atmosphere is 101,325 Pa = 1.01325 bar = 14.6959 psi, while 1 bar is exactly 100,000 Pa = 14.50377 psi. The difference is about 1.3%.
How do I convert kPa to psi?
Multiply kPa by 0.1450377, or divide by 6.894757. Example: 200 kPa ÷ 6.894757 = 29.0 psi. 100 kPa equals exactly 1 bar, which is 14.50377 psi.
What is the difference between mmHg and torr?
They are treated as identical here: 1 mmHg = 1 torr = 133.322387415 Pa. The torr was historically defined as 1/760 of a standard atmosphere, which differs from mmHg by less than one part in seven million.
How many mmHg are in 1 inHg?
Exactly 25.4 mmHg, since an inch is 25.4 mm. So a barometric reading of 30.00 inHg is 762 mmHg, and 29.92 inHg (1 atm) is about 760 mmHg.
What is kg/cm² and how does it relate to bar?
A kilogram-force per square centimeter (also called a technical atmosphere) equals 98,066.5 Pa, or about 0.980665 bar. It's common on older European and Asian gauges, where it's often read as roughly 1 bar.
Are these pressure conversion factors exact or approximate?
Most are exact by definition: 1 bar = 100,000 Pa, 1 atm = 101,325 Pa, 1 mmHg = 133.322387415 Pa, 1 kg/cm² = 98,066.5 Pa, and 1 psi = 6,894.757293 Pa. The inHg factor (3,386.389 Pa) is the standard value at 0 °C.
Do I need to worry about gauge versus absolute pressure?
The conversion factors are the same either way — only the reference zero differs. Gauge pressure measures above the local atmosphere, while absolute pressure includes it, so absolute = gauge + about 14.696 psi (1 atm) at sea level.