Why Convert Atmospheres to Bars?
Converting between atmospheres (atm) and bars (bar) is one of the most common pressure conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert atm to bar saves time and prevents errors.
Pressure conversions between atm and bar are critical in automotive maintenance, meteorology, and diving. Tire pressure recommendations differ by region — European cars typically specify bar while US vehicles use PSI. Weather services report atmospheric pressure in different units: hPa/mbar in most countries, mmHg (inHg) in the US. Scuba divers must understand ATM conversions to calculate safe diving depths and decompression schedules.
How to Convert Atmospheres to Bars
To convert atmospheres to bars, use the following formula:
bar = atm × 1.01325
Example: 1 atm = 1.01325 bar
For example, 5 atm = 5.06625 bar, 10 atm = 10.1325 bar, and 100 atm = 101.325 bar. Our calculator above performs this conversion instantly with full precision — no rounding errors.
Common Use Cases
- Standard atmospheric pressure at sea level: 1 atm = 1.01325 bar
- Pressure at 10 m underwater depth: 2 atm = 2.0265 bar
- Cabin pressure in a commercial airplane: 0.7 atm = 0.709275 bar
- Pressure at 40 m underwater depth: 5 atm = 5.06625 bar
Common Mistakes to Avoid
- Gauge vs absolute: Tire pressure gauges read relative to atmospheric pressure (gauge pressure). Add 1 atm (~14.7 psi) to get absolute pressure.
- Bar vs ATM confusion: 1 bar ≈ 0.987 atm — they're close but not equal. For precise work, don't interchange them.
- Unit proliferation: Pressure has many units (Pa, bar, psi, atm, mmHg, torr). Always confirm which unit your equipment uses.
Pro Tips
- Memorize the factor: 1 atm = 1.01325 bar. For quick mental math, remember this base conversion.
- Quick reference: 5 atm = 5.06625 bar · 10 atm = 10.1325 bar · 25 atm = 25.33125 bar · 50 atm = 50.6625 bar · 100 atm = 101.325 bar
- Bookmark this page: Save this converter for instant access. It works offline once loaded — no internet needed.
Atmospheres to Bars Conversion Table
| atm | bar |
|---|---|
| 0.01 atm | 0.0101325 bar |
| 0.1 atm | 0.101325 bar |
| 0.5 atm | 0.506625 bar |
| 1 atm | 1.01325 bar |
| 2 atm | 2.0265 bar |
| 5 atm | 5.06625 bar |
| 10 atm | 10.1325 bar |
| 20 atm | 20.265 bar |
| 50 atm | 50.6625 bar |
| 100 atm | 101.325 bar |
| 500 atm | 506.625 bar |
| 1000 atm | 1013.25 bar |
All values in this table are mathematically exact per NIST SP 811.