PSI to Gigapascals (psi to GPa)
1 pound per square inch equals 0.000006894757293 gigapascals (rounded).
How to convert pounds per square inch to gigapascals
To convert pounds per square inch to gigapascals, multiply the number of pounds per square inch by 0.000006894757293. The factor is rounded to 10 significant digits. To go the other way, multiply gigapascals by 145,037.7377 (rounded).
gigapascals = pounds per square inch × 0.000006894757293
Example: 10 pounds per square inch = 0.00006894757293 gigapascals.
About these units
Pound Per Square Inch (psi)
About 6,894.757 pascals. The common unit for tire pressure, hydraulics and gas pipelines in the US.
Unlike most pressure units, psi has no namesake: it simply spells out its own definition, one pound-force acting on one square inch, and it is based on avoirdupois units. Used mainly in the United States, it is about 6.895 kilopascals.
The letters after the unit matter. Psia is measured against a vacuum, while psig is measured against the surrounding air, so at sea level, where the atmosphere is about 14.7 psi, you add that amount to a gauge reading to get an absolute one. A bicycle tire at 65 psig is therefore at 79.7 psia, and the label psid means a difference between two pressures rather than a reference to ambient air.
Typical automobile tires are listed at about 32 psig, and road racing bicycle tires at about 120 psig. One standard atmosphere is 14.696 psi, which gives a feel for how many multiples of sea-level air those tire pressures represent.
1 pound per square inch = 6,894.757293 pascals (approximately).
Sources: Wikipedia: Pounds per square inch; Wikipedia: Standard atmosphere (unit)
Gigapascal (GPa)
One billion pascals. Used for the stiffness (Young's modulus) of materials; steel is about 200 GPa.
Blaise Pascal's name was attached to the SI unit of pressure in 1971, when the 14th General Conference on Weights and Measures adopted it for one newton per square metre. A gigapascal is a billion of them, 10^9 Pa, which is a size that makes sense only for solid materials and deep-Earth conditions, not for weather or tyres.
Materials scientists quote stiffness in it. Wikipedia's table of Young's modulus lists structural steel at about 200 GPa and diamond at 1,220 GPa, while geophysicists use gigapascals for tectonic stresses and pressures inside the planet. Atmospheric pressure of about 101,325 Pa is therefore about 0.0001 GPa, and one gigapascal is roughly 145,000 psi or 145 ksi. A gigapascal also equals one thousand megapascals, the unit in which concrete and steel strengths are usually written.
1 gigapascal = 1,000,000,000 pascals (exactly).
Sources: Wikipedia: Pascal (unit); Wikipedia: Pounds per square inch
Related conversions
- Gigapascals to PSI (reverse)
- PSI to pascals
- PSI to kilopascals
- PSI to bars
- PSI to standard atmospheres
- PSI to hectopascals
- PSI to megapascals
- PSI to millibars
- PSI to torr
- PSI to millimeters of mercury
- PSI to inches of mercury
- PSI to kilopounds per square inch
- PSI to millimeters of water
- Pascals to gigapascals
- Kilopascals to gigapascals
- Bars to gigapascals
- Standard atmospheres to gigapascals
See all pressure units.