PSIA to BAR
Convert psia into bar for gauges, specs, hydraulic notes, and pressure reference checks.
Quick Convert
Recent Conversions
Conversion Formula
Conversion Examples
PSIA to BAR Table
| PSIA | Bar |
|---|---|
| 1 | 0.0689475729 |
| 5 | 0.3447378647 |
| 10 | 0.6894757293 |
| 25 | 1.7236893233 |
| 50 | 3.4473786465 |
| 100 | 6.894757293 |
| 250 | 17.2368932325 |
| 500 | 34.473786465 |
| 1,000 | 68.94757293 |
| 2,500 | 172.368932325 |
Popular Conversions
- 1 psia = 0.0689475729 bar
- 5 psia = 0.3447378647 bar
- 10 psia = 0.6894757293 bar
- 25 psia = 1.7236893233 bar
- 50 psia = 3.4473786465 bar
- 100 psia = 6.894757293 bar
- 250 psia = 17.2368932325 bar
- 500 psia = 34.473786465 bar
What is PSIA and Bar?
PSIA
Definition: PSIA means pounds per square inch absolute and includes atmospheric pressure in the reading.
History/origin: Absolute-pressure notation became important once engineers needed to distinguish total pressure from gauge-only readings.
Current use: PSIA is used in thermodynamics, compressor work, gas laws, and sealed-system analysis.
Bar
Definition: A bar is a pressure unit equal to 100,000 pascals.
History/origin: It became common in industry because it sits near atmospheric pressure and is easy to scale.
Current use: Bar values are used in compressors, process plants, hydraulics, and equipment datasheets.
Related Pressure Conversions
Pressure values are commonly translated across SI, customary, and fluid-column units in the same job.
| Related Conversion | Factor or Rule | Formula |
|---|---|---|
| mmHg to kPa | × 0.133322387 | kPa = mmHg × 0.133322387 |
| MPa to psi | × 145.037738 | psi = MPa × 145.037738 |
| Pa to kPa | ÷ 1,000 | kPa = Pa ÷ 1,000 |
| Pa to psi | × 0.000145037738 | psi = Pa × 0.000145037738 |
| psi to bar | × 0.068947573 | bar = psi × 0.068947573 |
| psi to mmHg | × 51.714933 | mmHg = psi × 51.714933 |
| psia to psig | minus atmosphere | psig = psia – atmospheric pressure |
| psig to psia | plus atmosphere | psia = psig + atmospheric pressure |
Typical Use Cases
Frequently Asked Questions
Q: What is the difference between PSIG and PSIA?
A: PSIG is gauge pressure measured relative to atmospheric pressure, while PSIA is absolute pressure measured from a vacuum reference. That is why the two numbers are not interchangeable even before any other unit change is applied.
Q: What is a useful checkpoint for PSIA to BAR?
A: 1 psia equals 0.0689475729 bar, which is a practical reference when checking a gauge reading against an absolute-pressure calculation.
Q: Why does atmospheric pressure matter on these pages?
A: Because one scale includes the surrounding atmospheric pressure and the other does not. The zero point is different, so the converted number changes accordingly.
Q: When do engineers need PSIG and PSIA conversions?
A: They come up in compressors, vacuum systems, thermodynamic calculations, pressure vessels, process equipment, and any worksheet that mixes gauge and absolute pressure.
Q: How do I convert Bar back into PSIA?
A: psia = bar ÷ 0.06894757293. Use the reverse rule carefully so the gauge-versus-absolute reference stays consistent.
Q: Is this exact?
A: The calculation uses an exact factor.