Convert Millibars to Bar
1 millibar (mbar) equals 0.001 bar.
1 mbar = 0.001 bar
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk millibar to bar converter to paste a column from Excel.
How to Convert Millibar to Bar
- 1 mbar = 0.001 bar
- 1 bar = 1000 mbar
- Example: convert 15 mbar to bar: 15 mbar = 15 × 0.001 bar = 0.015 bar
Formula
bar = mbar ÷ 1000
Derivation from SI units:
- 1 mbar = 10⁻³ bar = 100 Pa = 1 hPa
- 1 bar = 10⁵ Pa (exact, by definition)
- 1 mbar = 100 Pa ÷ 100000 Pa per bar = 0.001 bar
Both units are defined exactly, so the factor is exact. Millibar definition: millibar; Bar definition: bar.
Worked examples
- A reading of 20 mbar converts to 0.02 bar.
20 mbar × 0.001 = 0.02 bar - A value of 900 mbar is 0.9 bar.
900 mbar × 0.001 = 0.9 bar
Millibar to Bar conversion table
| Millibars (mbar) | Bar |
|---|---|
| 0.1 mbar | 0.0001 bar |
| 0.5 mbar | 0.0005 bar |
| 1 mbar | 0.001 bar |
| 2 mbar | 0.002 bar |
| 5 mbar | 0.005 bar |
| 10 mbar | 0.01 bar |
| 20 mbar | 0.02 bar |
| 25 mbar | 0.025 bar |
| 37 mbar | 0.037 bar |
| 50 mbar | 0.05 bar |
| 100 mbar | 0.1 bar |
| 250 mbar | 0.25 bar |
| 500 mbar | 0.5 bar |
| 900 mbar | 0.9 bar |
| 950 mbar | 0.95 bar |
| 980 mbar | 0.98 bar |
| 1000 mbar | 1 bar |
| 1013.25 mbar | 1.01325 bar |
| 1020 mbar | 1.02 bar |
| 1050 mbar | 1.05 bar |
Where it's used
Millibars are used for weather maps and barometers (sea level ≈ 1013 mbar), while bar appear in compressed air and pneumatics (6–8 bar). Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.
Millibar to other pressure units
| Conversion | 1 mbar equals |
|---|---|
| millibar to pascal | 100 Pa |
| millibar to kilopascal | 0.1 kPa |
| millibar to megapascal | 0.0001 MPa |
| millibar to psi | 0.01450377377 psi |
| millibar to bar | 0.001 bar |
| millibar to decibar | 0.01 dbar |
| millibar to torr | 0.7500616827 Torr |
| millibar to millimeter of mercury | 0.7500615758 mmHg |
| millibar to millimeter of water | 10.19716213 mmH₂O |
| millibar to centimeter of water | 1.019716213 cmH₂O |
| millibar to inch of water | 0.401463076 inH₂O |
| millibar to inch of water (60 °F) | 0.401864652 inH₂O (60 °F) |
| millibar to inch of mercury | 0.0295299833 inHg |
| millibar to atmosphere | 0.0009869232667 atm |
| millibar to barye | 1000 Ba |
Frequently asked questions
How many bar are in 1 millibar?
1 mbar = 0.001 bar.
How do I convert millibars to bar?
Multiply the value in mbar by 0.001, or divide it by 1000. For example, 15 mbar × 0.001 = 0.015 bar.
Is the mbar to bar conversion exact?
Yes. Both units are defined exactly, and 1 mbar is exactly 0.001 bar.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "millibar".
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "bar".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Millibars to Bar. Retrieved October 17, 2026, from https://scientificconverters.com/pressure/millibar-to-bar/
IEEE
Scientific Converters, "Convert Millibars to Bar," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/pressure/millibar-to-bar/