A bar is exactly 100,000 pascals.
Bars to Gigapascals Converter — bar to GPa
Convert Bar (bar) to Gigapascal (GPa) using the exact conversion factor (1 bar = 0.0001 gigapascal). See the formula, worked examples, conversion table, history, and common uses.
Bars to Gigapascals converter
Converter
Pressure Converter
Convert pascals, bars, PSI, atmospheres, mercury columns, water columns, and engineering pressure units.
Context values
Some unit families need one extra value for a physically accurate result.
Gigapascal is 1000000000 pascal units.
Result = input x 100000 / 1e+9.
Pressure uses the pascal as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Bars to Gigapascals
Bar and Gigapascal both show up on pressure gauges — psi is standard on US tire and tool specifications, while bar is the everyday pressure unit across most of the rest of the world. Bar is most often used for tire pressure specifications outside the us.
Formula
gigapascals = bars × 0.0001
This factor comes from each unit's defined relationship to the category's base unit: 1 bar equals 100000 base units, and 1 gigapascal equals 1000000000 base units, so dividing one by the other gives the direct bar-to-gigapascal factor of 0.0001.
Simple example
1 bar × 0.0001 = 0.0001 GPa
1 bar = 0.0001 gigapascals.
Real-world example
35 bar × 0.0001 = 0.0035 GPa
35 bars = 0.0035 gigapascals.
Conversion table
| Bar (bar) | Gigapascal (GPa) |
|---|---|
| 1 bar | 0.0001 GPa |
| 5 bar | 0.0005 GPa |
| 10 bar | 0.001 GPa |
| 25 bar | 0.0025 GPa |
| 50 bar | 0.005 GPa |
| 100 bar | 0.01 GPa |
Reverse conversion: Gigapascal to Bar
0.0001 GPa × 10000 = 1 bar
0.0001 gigapascals = 1 bar.
bars = gigapascals × 10000
For a page dedicated to this direction, see Gigapascal to Bar.
Understanding the Bar
Bar (bar) measures pressure. A bar is defined as exactly 100,000 pascals, close to (but distinct from) one standard atmosphere (101,325 Pa). It is classified as a Non-SI metric unit accepted for use with SI.
Where it's used: Widely used in Europe and most of the world for tire pressure, weather, and industrial pressure
Uses of the Bar today
- Tire pressure specifications outside the US
- Meteorology (weather maps commonly use millibars, hPa)
- Industrial and hydraulic pressure ratings in metric-system countries
History of the Bar
The bar was proposed by Norwegian meteorologist Vilhelm Bjerknes around 1906 as a convenient round pressure unit close to atmospheric pressure, derived from the CGS unit system (one bar equals one million dynes per square centimeter).
Though not an SI unit, the bar remains in wide practical use, particularly in meteorology (as the millibar, now more often written as the equivalent hectopascal) and in tire and hydraulic pressure specifications across most of the world.
Historical origin. Bar 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.
Bar — sources
- BIPM SI Brochure — Non-SI units accepted for use with SI — Lists the bar among accepted non-SI pressure units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many gigapascals are in 1 bar?
1 bar equals 0.0001 gigapascals, using the exact defined conversion factor rather than an estimate.
How do I convert bar to gigapascal?
Multiply the bar value by 0.0001. The converter above does this instantly to whatever precision you set.
How do I convert gigapascal back to bar?
Use the reverse factor: 1 gigapascal equals 10,000 bars. You can also use the swap control in the converter above to flip the direction instantly.
What is a bar?
Bar (bar) measures pressure. A bar is defined as exactly 100,000 pascals, close to (but distinct from) one standard atmosphere (101,325 Pa). It is classified as a Non-SI metric unit accepted for use with SI.
What is a gigapascal?
Gigapascal (GPa) is a unit of pressure.
Is the bar to gigapascal conversion exact?
Yes. A bar is defined as exactly 100,000 pascals, close to (but distinct from) one standard atmosphere (101,325 Pa). 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 bar still used today?
Widely used in Europe and most of the world for tire pressure, weather, and industrial pressure