PSI to Bars Converter

The usual job here is matching gear labelled in psi to instructions, fittings or gauges that use bar. A few typical conversions:

• An air regulator set to 90 psi is 6.2053 bar.
• A compressor with a 150 psi cut-out is 10.3421 bar.
• A scuba cylinder or pressure washer rated at 3000 psi is 206.84 bar.
• A bike pump showing 100 psi is 6.8948 bar.

When a fitting or hose carries a maximum in bar, convert the psi you plan to run and compare like with like. Do not compare a psi rating against a bar limit by eye: the bar number is always about fourteen and a half times smaller.

One psi is 0.068948 bar in this converter, which is the same as dividing by 14.5038. Three ways to approximate it, with the error measured against the converter:

The ×0.07 shortcut is the friendliest for mental arithmetic: multiply by 7 and move the decimal two places. It overshoots by about 1.5%, so knock a little off the answer. For the 32 psi example the converter gives 2.2063 bar.

Because a bar is a much bigger unit, each decimal place carries more weight. Rounding 2.2063 bar to 2.2 drops only 0.09 psi, but rounding any value to one decimal of bar can move it by up to 0.05 bar, which is about 0.73 psi. For tyre pressures, keep two decimals if your gauge reads in hundredths of a bar. For compressor and diving pressures in the hundreds of psi, whole bar is plenty.

Some specs write psig for pressure above the surrounding air and psia for pressure above a vacuum. The same suffix carries over: psig becomes barg and psia becomes bara. The converter only rescales the number, so convert psig to barg and psia to bara, and never mix one of each in a single comparison.