Conversion tool
Convert pounds per square inch to megapascals instantly
Enter a value, see the result, copy it, and save a PDF snapshot.
Input
Type a value, then press Enter to calculate.
Result
0.000 MPa
Rounded for readability. Use the arrows to increase or decrease the number of shown digits.
Estimation mode
Enter your estimate in MPa, then reveal to compare.
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Disclaimer: Use calculations at your own risk. For critical applications, verify results against your governing standards/specifications.
How it works
We use MPa = psi x 0.00689475729317.
Exact relationship: 1 psi = 0.00689475729317 MPa.
Example: 10 psi = 0.069 MPa.
Notes: Results are rounded in the default view.
Examples
- 10 psi = 0.069 MPa
- 100 psi = 0.689 MPa
- 3000 psi = 20.684 MPa
FAQ
What physical quantity do pounds per square inch and megapascals express?
Pounds per square inch express pressure, meaning force distributed over an area rather than a simple force or distance quantity. Megapascals express pressure or stress using SI-derived units at a scale convenient for engineering materials and hydraulic systems.
What is the difference between pounds per square inch and megapascals?
Pounds per square inch and megapascals both express pressure, but they belong to different technical conventions and are favored in different industries and regional documentation systems.
What is the history of the pound per square inch?
PSI developed from customary force and area units and remains deeply embedded in U.S. pneumatics, hydraulics, tire pressure, and industrial equipment references.
What is the history of the megapascal?
Megapascals follow directly from the pascal within SI and became standard in engineering disciplines that use metric stress and pressure values.
Were the pound per square inch and megapascal discovered by a specific person?
PSI was not discovered by a single person; it emerged from established customary force and area units used together as a pressure measure. The megapascal is an SI-derived standardized unit rather than a discovery attributed to a single person.
Where are pounds per square inch and megapascals used in science and engineering?
PSI is common in hydraulics, pneumatics, pressure gauges, compressors, tire service, and U.S.-oriented industrial documentation. MPa is common in material strength data, hydraulic systems, stress calculations, and metric engineering specifications.
Why do pressure units matter in calculations?
Pressure units affect equipment ratings, seal selection, material limits, safety settings, and process controls. Keeping the unit visible helps prevent dangerous unit mistakes.
Can I trust this for critical calculations?
Use this for convenience and verify against your governing standard, equipment manual, or controlled specification for critical work. Pressure interpretation and safe limits depend on the system context.
References
- Exact constant used: 1 psi = 0.00689475729317 MPa.
- Pressure conversions are derived from consistent force-per-area relationships anchored to the pascal.