Millipascal is 0.001 pascal units.
Millipascals to Bars Converter — mPa to bar
Convert Millipascal (mPa) to Bar (bar) using the exact conversion factor (1 millipascal = 1e-8 bar). See the formula, worked examples, conversion table, history, and common uses.
Millipascals to Bars 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.
A bar is exactly 100,000 pascals.
Result = input x 0.001 / 100000.
Pressure uses the pascal as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Millipascals to Bars
Millipascal and Bar 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. Specifically: Millipascal is 0.001 pascal units, and a bar is exactly 100,000 pascals.
Formula
bars = millipascals × 1e-8
This factor comes from each unit's defined relationship to the category's base unit: 1 millipascal equals 0.001 base units, and 1 bar equals 100000 base units, so dividing one by the other gives the direct millipascal-to-bar factor of 1e-8.
Simple example
1 mPa × 1e-8 = 1e-8 bar
1 millipascal = 1e-8 bars.
Real-world example
35 mPa × 1e-8 = 3.5e-7 bar
35 millipascals = 3.5e-7 bars.
Conversion table
| Millipascal (mPa) | Bar (bar) |
|---|---|
| 1 mPa | 1e-8 bar |
| 5 mPa | 5e-8 bar |
| 10 mPa | 1e-7 bar |
| 25 mPa | 2.5e-7 bar |
| 50 mPa | 5e-7 bar |
| 100 mPa | 0.000001 bar |
Reverse conversion: Bar to Millipascal
1e-8 bar × 100000000 = 1 mPa
1e-8 bars = 1 millipascal.
millipascals = bars × 100000000
For a page dedicated to this direction, see Bar to Millipascal.
Understanding the Millipascal (mPa)
Millipascal is 0.001 pascal units.
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.
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 bars are in 1 millipascal?
1 millipascal equals 1e-8 bars, using the exact defined conversion factor rather than an estimate.
How do I convert millipascal to bar?
Multiply the millipascal value by 1e-8. The converter above does this instantly to whatever precision you set.
How do I convert bar back to millipascal?
Use the reverse factor: 1 bar equals 100,000,000 millipascals. You can also use the swap control in the converter above to flip the direction instantly.
What is a millipascal?
Millipascal (mPa) is a unit of pressure.
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.
Is the millipascal to bar 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.