Convert Millibars to Kilopascals

Formula

kPa = mbar ÷ 10

Derivation from SI units:

• 1 mbar = 10⁻³ bar = 100 Pa = 1 hPa
• 1 kPa = 10³ Pa
• 1 mbar = 100 Pa ÷ 1000 Pa per kPa = 0.1 kPa

Both units are defined exactly, so the factor is exact. Millibar definition: millibar; Kilopascal definition: kilopascal.

Worked examples

1. A reading of 20 mbar converts to 2 kPa.
   20 mbar × 0.1 = 2 kPa
2. A value of 900 mbar is 90 kPa.
   900 mbar × 0.1 = 90 kPa

Where it's used

Millibars are used for weather maps and barometers (sea level ≈ 1013 mbar), while kilopascals appear in tyre pressure outside the United States (about 200–250 kPa for cars). Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.

Millibar to other pressure units

Frequently asked questions

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".
• The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.