A bar is a metric unit of pressure but is not approved as part of the International System of Units (SI). The bar is defined using the SI derived unit Pascal as 1 bar ≡ 100,000 Pa.
1 bar = 105 Pa
The units derived from the bar include the megabar (symbol: Mbar), kilobar (symbol: kbar), decibar (symbol: bar), centibar (symbol: cbar), and millibar (symbol: mbar or mb).