Stress converter
Mechanical stress and material strength (yield, tensile, elastic modulus). Stress has the same units as pressure: 1 N/mm² is exactly 1 MPa, and 1 ksi is exactly 1 000 psi.
1 pound per square inch = 0.0068948 megapascals
How it’s calculated
MPa = psi ÷ 145.0377377
- Divide the value in pounds per square inch by 145.0377377.
- Equivalently, multiply by 0.006894757293.
- 1 psi = 0.006894757293 MPa · 1 MPa = 145.0377377 psi
Show worked solutionFactor, unit cancellation and rounding, step by step
Find the conversion factor
By definition 1 psi = 6894.75729316836 Pa and 1 MPa = 1000000 Pa, so 1 MPa = 145.037737730209 psi. Source: NIST SP 811 / Handbook 44; BIPM SI Brochure (9th ed.) (SI prefixes and accepted units).
Multiply by the factor written as a fraction
Put psi in the denominator so it cancels, leaving MPa.
Calculate (unrounded)
Round the answer
Rounded to 5 significant figures.
Answer: 0.0068948 MPa
1 psi in other units
Batch convert psi → MPa
- 1 psi = 0.0068948 MPa
- 5 psi = 0.034474 MPa
- 10 psi = 0.068948 MPa
- 25 psi = 0.17237 MPa
Common stress conversions
- Pounds per square inch to megapascals
- Megapascals to pounds per square inch
- Kips per square inch to megapascals
- Megapascals to kips per square inch
- Gigapascals to pounds per square inch
- Gigapascals to kips per square inch
- Newtons per square millimetre to pounds per square inch
- Pounds-force per square foot to kilopascals
Stress units and exact definitions
| Unit | System | Definition |
|---|---|---|
| Megapascal (MPa) | SI (metric) | 1 MPa = 1000000 Pa |
| Gigapascal (GPa) | SI (metric) | 1 GPa = 1000000000 Pa |
| Kilopascal (kPa) | SI (metric) | 1 kPa = 1000 Pa |
| Pascal (Pa) | SI (metric) | Base unit |
| Newton per square millimetre (N/mm²) | SI (metric) | 1 N/mm² = 1000000 Pa |
| Pound per square inch (psi) | US & imperial (identical) | 1 psi = 6894.757293 Pa |
| Kip per square inch (ksi) | US customary | 1 ksi = 6894757.293 Pa |
| Pound-force per square foot (lbf/ft²) | US & imperial (identical) | 1 lbf/ft² = 47.88025898 Pa |
| Bar (bar) | metric (non-SI) | 1 bar = 100000 Pa |
| Kilogram-force per cm² (kgf/cm²) | other | 1 kgf/cm² = 98066.5 Pa |
| Hectopascal (hPa) | SI (metric) | 1 hPa = 100 Pa |
| Millibar (mbar) | metric (non-SI) | 1 mbar = 100 Pa |
| Standard atmosphere (atm) | other | 1 atm = 101325 Pa |
| Millimetre of mercury (mmHg) | other | 1 mmHg = 133.3223874 Pa |
| Torr (Torr) | other | 1 Torr = 133.3223684 Pa |
| Inch of mercury (inHg) | US customary | 1 inHg = 3386.38864 Pa |
| Inch of water (inH₂O) | US customary | 1 inH₂O = 249.08891 Pa |
Pounds per square inch to megapascals conversion table
| Pounds per square inch (psi) | Megapascals (MPa) |
|---|---|
| 1 psi | 0.0068948 MPa |
| 5 psi | 0.034474 MPa |
| 10 psi | 0.068948 MPa |
| 20 psi | 0.1379 MPa |
| 25 psi | 0.17237 MPa |
| 30 psi | 0.20684 MPa |
| 36 psi | 0.24821 MPa |
| 40 psi | 0.27579 MPa |
| 50 psi | 0.34474 MPa |
| 60 psi | 0.41369 MPa |
| 75 psi | 0.51711 MPa |
| 100 psi | 0.68948 MPa |
| 150 psi | 1.0342 MPa |
| 200 psi | 1.379 MPa |
| 250 psi | 1.7237 MPa |
| 300 psi | 2.0684 MPa |
| 355 psi | 2.4476 MPa |
| 400 psi | 2.7579 MPa |
| 500 psi | 3.4474 MPa |
| 1,000 psi | 6.8948 MPa |
Frequently asked questions
Which stress units can I convert?
megapascals (MPa), gigapascals (GPa), kilopascals (kPa), pascals (Pa), newtons per square millimetre (N/mm²), pounds per square inch (psi), kips per square inch (ksi), pounds-force per square foot (lbf/ft²), bar (bar), kilograms-force per cm² (kgf/cm²).
How accurate are the results?
Every unit is stored with its exact defining factor (NIST SP 811, NIST Handbook 44 or the BIPM SI Brochure). Calculations use double-precision arithmetic and are rounded only for display, to 5 significant figures by default (trailing zeros dropped, so 1 km shows as 1000 m). You can choose Auto (up to 10 digits), fixed decimals or more significant figures, or switch to scientific or engineering notation.
Is stress measured in the same units as pressure?
Yes. Stress and pressure are both force per area, so they share units: 1 MPa = 1 N/mm² exactly, and 1 ksi = 1 000 psi ≈ 6.894757 MPa. Engineers usually quote stress in MPa, N/mm², psi or ksi.