Pressure Converter

Tyres are labelled in psi or bar, weather in millibars or hectopascals, blood pressure in mmHg, and engineering drawings in kilopascals. All eight units below convert through the pascal, the SI unit.

Handy anchors: 1 bar is 100 kPa and very nearly one atmosphere (true atmospheric pressure is 101.325 kPa). 1 bar is about 14.5 psi, so a 32 psi tyre is roughly 2.2 bar. And a millibar and a hectopascal are the same size, which is why weather maps can switch between them without the numbers changing.

Amount

From

1 PSI = 0.068947573 Bar

Converted in your browser. Nothing is sent anywhere.

This page’s converter uses ordinary JavaScript numbers, so long results round like any web calculator. CalcBoard’s in-app converter uses exact decimal arithmetic and works with no connection at all.

Common pressure conversions

Common pressure conversions for 1, 5 and 100 units
Conversion	1	5	100
PSI → Bar	0.068947573	0.34473786	6.8947573
Bar → PSI	14.503774	72.518869	1450.3774
Atmosphere → Kilopascal	101.325	506.625	10132.5
PSI → Kilopascal	6.8947573	34.473786	689.47573
mmHg → Kilopascal	0.13332239	0.66661194	13.332239
Bar → Atmosphere	0.98692327	4.9346163	98.692327

Every pressure unit CalcBoard converts

All 8 units in this category, with the exact factor each one uses to reach the base unit (pascal). These are the same constants the app computes with.

Every pressure unit with its conversion factor and tier
Unit	In pascals	Tier
Pascal	1	Premium
Kilopascal	1000	Premium
Bar	100000	Premium
Millibar	100	Premium
Atmosphere	101325	Premium
PSI	6894.75729317	Premium
mmHg	133.322387415	Premium
Torr	133.322368421	Premium

Convert without a browser

This page needs a connection. The CalcBoard app does the same conversions offline, with exact decimal arithmetic, and puts the converter next to a working calculator — so you can convert a measurement in one panel and immediately use it in a formula in the next, without copying anything by hand.

Free vs. Premium, honestly: the free app includes 2 panels, basic mode, 3 converter categories, and your last 10 history entries — no ads, no time limits. A one-time $2.99 purchase (no subscription) unlocks scientific and programmer modes, up to 8 panels, the shared value tray, all 10 converter categories, full history with search and CSV export, and all themes and button styles.

Frequently Asked Questions

How many psi is 1 bar?

One bar is about 14.5037738 psi. So a tyre at 2.2 bar is about 32 psi, and 2.5 bar is about 36 psi.

Is a bar the same as an atmosphere?

Almost, but not exactly. One atmosphere is 101,325 pascals; one bar is 100,000 pascals. An atmosphere is about 1.3% higher, which matters in lab and diving contexts but not for tyres.

Why is blood pressure measured in mmHg?

It dates from mercury column manometers, where pressure was read as the height the mercury rose. One mmHg is about 133.322 pascals, and the unit stuck long after the mercury instruments went away.

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