Pounds per square inch.
PSI to Gigapascals Converter — psi to GPa
Convert PSI (psi) to Gigapascal (GPa) using the exact conversion factor (1 psi = 0.0000068948 gigapascal). See the formula, worked examples, conversion table, history, and common uses.
PSI to Gigapascals converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
Gigapascal is 1000000000 pascal units.
Result = input x 6894.757293 / 1e+9.
Stress Pressure units are compatible.
Reserved above the conversion cards and below the converter.
About Converting PSI to Gigapascals
PSI and Gigapascal both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. PSI is most often used for tire pressure specifications in the us.
Formula
gigapascals = psi × 0.00000689475729317
This factor comes from each unit's defined relationship to the category's base unit: 1 psi equals 6894.75729317 base units, and 1 gigapascal equals 1000000000 base units, so dividing one by the other gives the direct psi-to-gigapascal factor of 0.00000689475729317.
Simple example
1 psi × 0.000006894757293 = 0.0000068948 GPa
1 psi = 0.0000068948 gigapascals.
Real-world example
100 psi × 0.000006894757293 = 0.0006894757 GPa
100 psi = 0.0006894757 gigapascals.
Conversion table
| PSI (psi) | Gigapascal (GPa) |
|---|---|
| 1 psi | 0.0000068948 GPa |
| 10 psi | 0.0000689476 GPa |
| 50 psi | 0.0003447379 GPa |
| 100 psi | 0.0006894757 GPa |
| 500 psi | 0.0034473786 GPa |
| 1,000 psi | 0.0068947573 GPa |
Reverse conversion: Gigapascal to PSI
0.0000068948 GPa × 145037.7377 = 1.000006194 psi
0.0000068948 gigapascals = 1.000006194 psi.
psi = gigapascals × 145037.73773
For a page dedicated to this direction, see Gigapascal to PSI.
Understanding the PSI
PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.
Where it's used: United States (standard pressure unit for tires, tools, and plumbing)
Uses of the PSI today
- Tire pressure specifications in the US
- Hydraulic and pneumatic system ratings
- Plumbing, compressed-air tools, and industrial equipment ratings
History of the PSI
PSI is a derived unit from the pound-force and the inch, both themselves standardized through English and later international agreements rather than invented as a pressure unit from scratch.
It became the default pressure unit in US engineering as pound-force and inch-based measurement dominated American industry through the 19th and 20th centuries, and it remains in everyday use for tires and tools even as most other measurements in the US context stay imperial.
Historical origin. PSI was not the invention of a single named person; it developed through the process described above.
Understanding the Gigapascal (GPa)
Gigapascal is 1000000000 pascal units.
PSI — sources
- NIST Special Publication 811 — Guide for the Use of the International System of Units — Documents conversion factors for psi and other US customary pressure units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many gigapascals are in 1 psi?
1 psi equals 0.0000068948 gigapascals, using the exact defined conversion factor rather than an estimate.
How do I convert psi to gigapascal?
Multiply the psi value by 0.000006894757293. The converter above does this instantly to whatever precision you set.
How do I convert gigapascal back to psi?
Use the reverse factor: 1 gigapascal equals 145,037.7377 psi. You can also use the swap control in the converter above to flip the direction instantly.
What is a psi?
PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.
What is a gigapascal?
Gigapascal (GPa) is a unit of engineering.
Is the psi to gigapascal conversion exact?
Yes. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the psi still used today?
United States (standard pressure unit for tires, tools, and plumbing)
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.