bar Other
Measures: Pressure — how concentrated a push
Bar
Roughly one atmosphere of pressure.
PressureHow it's defined
Defined as exactly 100,000 pascals — deliberately close to average sea-level air pressure (101,325 Pa), which is why tire gauges and dive computers like it.
1 bar = 100,000 Pa — exact1 atm = 101,325 Pa — exact, and slightly more
Convert — honestly
bar equals
100000 Pa
Pascal · factor exact — the base unit itself
14.5037738 psi
Pound per square inch · factor exact — exact (derived from lb, in, g₀)
Conversions run through the pascal using the stated factors — no rounding beyond display precision, and every factor says whether it's exact or measured.
Where you meet it
- Espresso machines (9 bar) and scuba tanks
- European tire pressure gauges
Other ways to measure pressure
Source
This page is an authored summary of the authoritative definition — checkable one click away.
NIST Special Publication 811 — Guide for the Use of the SI