Atmosphere to Bar Conversion Chart
| Standard Atmosphere (atm) | Bar (bar) | Reference Benchmark | Formula Step |
|---|---|---|---|
| 0.1 atm | 0.1013 bar | Rough Low-Pressure Vacuum Desiccation Chamber | 0.1 × 1.01325 = 0.101325 bar |
| 0.25 atm | 0.2533 bar | High-Altitude Barometric Stratosphere Horizon | 0.25 × 1.01325 = 0.253313 bar |
| 0.5 atm | 0.5066 bar | Mount Everest Summit Ambient Atmospheric Pressure | 0.5 × 1.01325 = 0.506625 bar |
| 1 atm | 1.0133 bar | Standard Mean Sea-Level Atmospheric Baseline | 1 × 1.01325 = 1.01325 bar |
| 1.5 atm | 1.5199 bar | Commercial Building Fire Sprinkler Standby Supply | 1.5 × 1.01325 = 1.519875 bar |
| 2 atm | 2.0265 bar | Ten-Meter Underwater Scuba Gauge Absolute Pressure | 2 × 1.01325 = 2.0265 bar |
| 2.5 atm | 2.5331 bar | Municipal Potable Water Distribution Mains Line | 2.5 × 1.01325 = 2.533125 bar |
| 3 atm | 3.0398 bar | Twenty-Meter Underwater Scuba Absolute Level | 3 × 1.01325 = 3.03975 bar |
| 4 atm | 4.053 bar | Thirty-Meter Ocean Diving Hydrostatic Benchmark | 4 × 1.01325 = 4.053 bar |
| 5 atm | 5.0663 bar | Forty-Meter Deep Technical Diving Hydrostatic Depth | 5 × 1.01325 = 5.06625 bar |
| 6 atm | 6.0795 bar | Standard Industrial Pneumatic Distribution Header | 6 × 1.01325 = 6.0795 bar |
| 8 atm | 8.106 bar | Heavy Commercial Truck Air Brake Reservoir | 8 × 1.01325 = 8.106 bar |
| 10 atm | 10.1325 bar | Commercial Espresso Pump Grouphead Delivery | 10 × 1.01325 = 10.1325 bar |
| 15 atm | 15.1988 bar | Industrial Steam Heat Recovery Boiler Header | 15 × 1.01325 = 15.19875 bar |
| 20 atm | 20.265 bar | Subsea Deep Ocean Exploration ROV Trench Chamber | 20 × 1.01325 = 20.265 bar |
Standard Atmosphere to Bar Formula & Unit Definitions
Under the 1954 CGPM definition, 1 standard atmosphere equals exactly 101,325 pascals, which corresponds to exactly 1.01325 bar (101,325 ÷ 100,000). Converting atmospheres to bar is performed by multiplying the atmosphere figure by 1.01325. To reverse the calculation from bar back to atmospheres, divide the bar value by 1.01325 (or multiply by 0.986923).
Quick Estimation: Multiply the atmosphere reading by 1.013 (or add approximately 1.3% to the atmosphere value). For example, 5 atm × 1.01325 ≈ 5.07 bar; 10 atm ≈ 10.13 bar.
Standard Atmosphere (atm)
Physical Standard Baseline- Creator & Origin: Codified by the 10th CGPM in 1954 as the permanent international anchor for mean sea-level pressure.
- Standard Definition: Defined as exactly 101,325 pascals, equivalent to 760 torr or 1.01325 bar.
- Everyday Focus: Underwater dive tables, chemical gas phase equilibria, high-pressure autoclaves, and meteorological physics.
Bar Standard (bar)
Metric Engineering Unit- Creator & Origin: Formulated in 1909 by William Napier Shaw and adopted across Continental European engineering in 1914.
- Standard Definition: Defined as exactly 100,000 pascals (10⁵ N/m² or 100 kPa), representing round decimal metric pressure.
- Everyday Focus: European automotive tire inflators, workshop air compressors, espresso machines, and hydraulic rams.
Frequently Asked Questions
Q.How do you convert atmospheres to bar?
Multiply the atmosphere value by 1.01325.
Q.How many bar are in 1 standard atmosphere?
There are exactly 1.01325 bar in one standard atmosphere (1 atm = 1.01325 bar = 101,325 Pa).
Q.What is the reciprocal conversion for this tool?
The direct reverse tool is the Bar to Atmospheres Converter, where 1 bar equals approximately 0.986923 atm.
Q.Why is 1 atm slightly more than 1 bar?
The bar is an arbitrary decimal unit defined as exactly 100,000 Pa, while 1 atm represents actual average sea-level atmospheric weight (101,325 Pa).