Pressure Unit Converter
Convert pressure between pascals, kilopascals, bar, psi, atmospheres, and millimeters of mercury.
- Converted value
- 14.695949
How it works
Every unit converts to pascals first using exact, internationally defined factors — 1 bar = 100,000 Pa, 1 atm = 101,325 Pa, 1 psi = 6,894.757293168 Pa (a pound-force per square inch), and 1 mmHg = 133.322387415 Pa (the conventional millimeter of mercury) — then from pascals to the target unit. Converting through a common base unit keeps every conversion pair exact.
These units show up in different everyday contexts: psi for tire pressure, bar and atm for weather and diving, mmHg for blood pressure and barometric readings, and pascals (the SI unit) underlying all of them.
FAQ
Why is atmospheric pressure sometimes given as 1 atm and other times as 1013.25 hPa or 14.7 psi?
They're the same standard atmosphere expressed in different units — 1 atm is defined as exactly 101,325 Pa, which is 1013.25 hectopascals (the unit meteorologists usually report) and approximately 14.696 psi. This calculator converts between any of these directly.