Quick example
Convert 1 bar to psi
One bar is exactly 100,000 pascals. Divide by approximately 6,894.757293168 pascals per psi to get 14.503773773 psi.
Quick reference
Common pressure conversions
| Starting pressure | Equivalent |
|---|---|
| 1 kPa | 0.145038 psi |
| 100 kPa | 14.5038 psi |
| 1 MPa | 10 bar |
| 1 bar | 100 kPa |
| 1 psi | 6.89476 kPa |
| 1 atm | 101.325 kPa |
| 1 atm | 14.6959 psi |
| 760 mmHg | Approximately 101.325 kPa |
Unit definitions
Metric, customary, and atmospheric pressure
Pascal units
The pascal is the SI pressure unit, equal to one newton per square meter. Kilopascals and megapascals scale it by 1,000 and 1,000,000.
Bar
One bar is exactly 100,000 pascals. It is common in weather, industrial systems, diving, and vehicle specifications.
Psi
Pounds per square inch is widely used for tire pressure, compressed gases, hydraulics, and other US customary measurements.
Atmosphere and mmHg
A standard atmosphere is exactly 101,325 pascals. Conventional mmHg is used in fields including medicine and vacuum measurement.
Pressure reference
Gauge pressure is not absolute pressure
A unit conversion changes only the unit, not the reference point. Gauge pressure is measured relative to local atmospheric pressure, while absolute pressure is measured relative to a perfect vacuum. Negative gauge or differential readings are valid, so this converter accepts them; negative absolute pressure is not physically meaningful. The converter does not add or subtract atmospheric pressure.
Common questions
Pressure conversion FAQ
How many psi are in one bar?
One bar equals approximately 14.5038 pounds per square inch.
How do I convert psi to kPa?
Multiply psi by approximately 6.894757293. For example, 30 psi is about 206.843 kPa.
What is one atmosphere in kPa and psi?
One standard atmosphere is exactly 101.325 kPa and approximately 14.6959 psi.
Are mmHg and torr exactly the same?
No. They are extremely close but use different conventional definitions. This tool uses 1 mmHg = 133.322387415 Pa; one torr is exactly one standard atmosphere divided by 760.
Can pressure be negative?
Gauge and differential pressure can be negative relative to a reference. Absolute pressure cannot be below zero. This tool converts the entered value without changing its reference type.