Convert Bar to Decibars

Formula

dbar = bar × 10

Derivation from SI units:

• 1 bar = 10⁵ Pa (exact, by definition)
• 1 dbar = 10⁻¹ bar = 10⁴ Pa
• 1 bar = 100000 Pa ÷ 10000 Pa per dbar = 10 dbar

Both units are defined exactly, so the factor is exact. Bar definition: bar; Decibar definition: decibar.

Worked examples

1. A reading of 2 bar converts to 20 dbar.
   2 bar × 10 = 20 dbar
2. A value of 10 bar is 100 dbar.
   10 bar × 10 = 100 dbar

Where it's used

Bar are used for compressed air and pneumatics (6–8 bar), while decibars appear in oceanography: CTD instruments report sea pressure in dbar. Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.

Bar 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, "bar".
• 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", with SI prefix deci (10⁻¹).

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