PSI to Bar Converter
Convert from Pounds per Square Inch (PSI) to Bar
Understanding PSI and Bar
PSI is a unit of pressure in the imperial and US customary measurement systems.
- Defined as one pound-force applied to one square inch of area
- Standard atmospheric pressure is approximately 14.7 PSI
- Commonly used for tire pressure, hydraulic systems, and gas pressure
- Widely used in the United States and countries using imperial units
The bar is a metric unit of pressure, though not part of the International System of Units (SI).
- 1 bar = 100,000 pascals (Pa)
- 1 bar = 14.5038 PSI
- Approximately equal to atmospheric pressure at sea level (1.013 bar)
- Widely used in meteorology, engineering, and industrial applications
Conversion Formula
PSI to Bar:
Bar = PSI × 0.0689476
To convert from PSI to bar, multiply the PSI value by approximately 0.0689476.
Bar to PSI:
PSI = Bar × 14.5038
To convert from bar to PSI, multiply the bar value by approximately 14.5038.
PSI to Bar Conversion Table
| Pounds per Square Inch (PSI) | Bar |
|---|---|
| 5 | 0.3447 |
| 10 | 0.6895 |
| 15 | 1.0342 |
| 20 | 1.3790 |
| 25 | 1.7237 |
| 30 | 2.0684 |
| 35 | 2.4132 |
| 40 | 2.7579 |
| 45 | 3.1026 |
| 50 | 3.4474 |
Historical Context and Applications
Historical Development
The bar unit was introduced by Vilhelm Bjerknes in 1900 for meteorological use. It was designed to be close to atmospheric pressure at sea level (1.013 bar) for convenient measurement. The PSI unit developed during the industrial revolution in England and became standardized with mechanical engineering advancements. The bar unit gained popularity in Europe and scientific applications, while PSI remained dominant in American engineering contexts.
Common Applications
- PSI: Widely used in the United States for tire pressure, hydraulic systems, industrial processes, and HVAC systems. The standard unit for pressure gauges in American engineering.
- Bar: Common in European industrial applications, meteorology, and natural gas distribution. The preferred unit in many international contexts and engineering standards outside the US.
Practical Examples
- Standard atmospheric pressure: 14.7 PSI (1.013 bar)
- Car tire pressure: 30-35 PSI (2.07-2.41 bar)
- Bicycle tire pressure: 50-90 PSI (3.45-6.20 bar)
- Espresso machine pressure: 9 bar (130.5 PSI)
- Scuba tank pressure: 200-300 bar (2,900-4,350 PSI)
- Enter your value in the PSI field
- The converter instantly displays the equivalent in bar
- Use the swap button to convert from bar to PSI instead
- Results are displayed with 6 decimal places for precision
- For quick reference without calculations, refer to the conversion table above
This converter is particularly useful for engineers working across international standards, as well as for anyone needing to translate between American and European pressure specifications for equipment and systems.