Unit converter · calculator
PSI to Bar & Bar to PSI Pressure Converter
Convert pressure between pounds per square inch and bar in either direction.
Method record
What this calculator measures
PSI and bar are both pressure units. Converting between them preserves the same physical pressure and does not imply a flow rate.
bar = PSI × 0.0689475729 Use it correctly
Calculation steps
- Enter the PSI value.
- Read bar and kPa equivalents.
- Keep enough significant figures for the source measurement.
Applicability
Use the model within its limits
Do not use a pressure-unit conversion as a PSI-to-GPM calculation. Flow needs a system model.
What this result represents
- System
- Unit converter
- Formula
- bar = PSI × 0.0689475729
- Review
- Verify safety-sensitive work with qualified guidance.
Worked Field Example
Worked Example: Metric Booster Pump Pressure Conversion
Field Scenario: Converting an imported European pump station test reading of 4.25 bar into US Customary PSI and kilopascals.
Given Input Parameters
Step-by-Step Mathematical Solution
- Pressure in PSI = 4.25 × 14.50377 ≈ 61.64 PSI.
- Pressure in kPa = 4.25 × 100 = 425.0 kPa.
- Equivalent Head of Water = 61.64 × 2.307 ≈ 142.2 feet of head.
61.64 PSI (425.0 kPa, 142.2 ft head).
Professional Guidance: Verify whether gauge pressure (barg / psig) or absolute pressure (bara / psia) is specified on technical submittals.
Engineering Standard Reference
Standard Industrial Pressure Conversion Lookup Table
Direct pressure equivalents across US Customary and Metric engineering units:
| PSI (Pounds / Sq Inch) | Bar (Metric) | Kilopascals (kPa) | Megapascals (MPa) | Typical System Baseline |
|---|---|---|---|---|
| 10 PSI | 0.69 Bar | 68.9 kPa | 0.069 MPa | Low gravity feed / drip irrigation system |
| 15 PSI | 1.03 Bar | 103.4 kPa | 0.103 MPa | Standard atmospheric baseline (1 atm = 14.7 PSI) |
| 30 PSI | 2.07 Bar | 206.8 kPa | 0.207 MPa | Well pump cut-in / minimum sprinkler head supply |
| 50 PSI | 3.45 Bar | 344.7 kPa | 0.345 MPa | Standard municipal residential water service line |
| 60 PSI | 4.14 Bar | 413.7 kPa | 0.414 MPa | Residential well pressure tank cut-out setting |
| 80 PSI | 5.52 Bar | 551.6 kPa | 0.552 MPa | Plumbing code maximum allowable without PRV regulator |
| 150 PSI | 10.34 Bar | 1,034.2 kPa | 1.034 MPa | Commercial fire sprinkler hydro test pressure |
| 3,000 PSI | 206.84 Bar | 20,684 kPa | 20.68 MPa | Commercial pressure washer / hydraulic power pack |
Engineering Note: Exact mathematical multipliers: 1 PSI = 0.06894757 Bar = 6.894757 kPa. 1 Bar = 14.50377 PSI.
Engineering FAQs
Frequently Asked Questions
What is the exact mathematical conversion between PSI and bar?
1 PSI = 0.06894757 bar (exactly 6,894.757 Pascals). Conversely, 1 bar = 100,000 Pascals = 14.50377 PSI. Standard atmospheric pressure at sea level is 14.696 PSI (1.01325 bar).
What is the difference between gauge pressure (psig / bar) and absolute pressure (psia / bar a)?
Gauge pressure measures pressure relative to local ambient atmosphere (a zero reading means open to air). Absolute pressure includes atmospheric pressure: psia = psig + 14.7, and bar(a) = bar(g) + 1.013.
When is kilopascal (kPa) or megapascal (MPa) preferred over bar?
In formal SI engineering (ISO standards and European structural codes), Pascals, kPa (1 bar = 100 kPa), and MPa (10 bar = 1 MPa) are standard coherent SI units, while bar is an accepted non-SI metric unit common in fluid power.