Enter the value and select from pascals, kilopascals, bar, psi, atmospheres, millimeters of mercury and inches of mercury. Gauge pressure is relative to surrounding air; absolute pressure uses a vacuum reference. One atmosphere is 101,325 pascals, about 14.696 psi and 760 millimeters of mercury.
Confirm the unit printed on the gauge dial.
Pressure Converter: worked example
| Pressure to convert | 32 |
|---|---|
| Starting unit | PSI |
| Requested unit | Kilopascals |
| Converted value | 220.6 |
| 1 unit of "from" in "to" units | 6.9 |
Pressure Converter: formula
Common error: Assuming a gauge reading is absolute. A tire gauge reads pressure above the air around it, so adding the atmosphere gives a very different number.
The converter applies multiplicative unit factors only. It does not add a gauge-to-absolute offset, determine pressure from altitude or correct for temperature. Liquid-column units require a stated convention, represented by the listed factors.
Keep a negative gauge reading’s sign when applicable; a vacuum reference and an ambient-air reference are different choices.
Pressure Converter: changing Pressure to convert
| Pressure to convert | Converted value | 1 unit of "from" in "to" units |
|---|---|---|
| 26 | 179.3 | 6.9 |
| 29 | 199.9 | 6.9 |
| 32 (example) | 220.6 | 6.9 |
| 35 | 241.3 | 6.9 |
| 38 | 262 | 6.9 |
Pressure Converter: compare input ranges
| Input | Tested from | To | Converted value: low input | Converted value: high input | Swing |
|---|---|---|---|---|---|
| Requested unit | Pascals | Inches of mercury | 220,632.2 | 65.2 | 220,567.1 (99999%) |
| Starting unit | Pascals | Inches of mercury | 0.032 | 108.4 | 108.3 (1470%) |
| Pressure to convert | 29 | 35 | 199.9 | 241.3 | 41.4 (19%) |
Pressure Converter: individual input comparisons
| Input | Value | Converted value | 1 unit of "from" in "to" units |
|---|---|---|---|
| Pressure to convert | 26 | 179.3 | 6.9 |
| 29 | 199.9 | 6.9 | |
| 32 | 220.6 | 6.9 | |
| 35 | 241.3 | 6.9 | |
| 38 | 262 | 6.9 | |
| Starting unit | Pascals | 0.032 | 0.001 |
| Kilopascals | 32 | 1 | |
| Bar | 3,200 | 100 | |
| PSI | 220.6 | 6.9 | |
| Atmospheres | 3,242.4 | 101.3 | |
| mmHg (torr) | 4.3 | 0.133 | |
| Inches of mercury | 108.4 | 3.4 | |
| Requested unit | Pascals | 220,632.2 | 6,894.8 |
| Kilopascals | 220.6 | 6.9 | |
| Bar | 2.2 | 0.069 | |
| PSI | 32 | 1 | |
| Atmospheres | 2.2 | 0.068 | |
| mmHg (torr) | 1,654.9 | 51.7 | |
| Inches of mercury | 65.2 | 2 |
Pressure Converter: which assumptions move the result?
Pressure Converter: values and definitions
| Quantity and definition | Value used |
|---|---|
| Pressure to convert | 32 |
| Starting unit — Unit to convert from. | PSI |
| Requested unit — Unit to convert to. | Kilopascals |
| Converted value | 220.6 |
| 1 unit of "from" in "to" units | 6.9 |
Unit Conversion calculators: Power Converter Calculator, Height Converter Calculator, Angle Converter Calculator, Data Rate Converter Calculator, Force Converter Calculator, Torque Converter Calculator.
Pressure appears in a different unit in nearly every trade. Tires read in PSI, weather in inches of mercury or millibars, engineering in pascals, blood pressure in millimeters of mercury. A tire at 32 PSI is about 220.6 kilopascals.
One atmosphere is 14.7 PSI or 101.3 kilopascals, which makes it a handy mental anchor when a gauge reads in an unfamiliar unit. Reference values: one atmosphere is 101.325 kilopascals, 14.696 psi and 760 mmHg, and one bar is 100 kilopascals or about 14.5 psi. A typical car tire at 32 psi is about 2.2 bar.
Note whether the gauge shows gauge pressure or absolute pressure. Gauge pressure ignores the atmosphere, and the difference is about 14.7 PSI.
Convert force on the force converter, energy on the energy converter and volume on the volume converter. The combined gas law calculator relates pressure, volume and temperature, and the mean arterial pressure page uses millimeters of mercury. The tire size calculator relates to inflation and fit.
Does changing psi to bar turn gauge pressure into absolute pressure?
No. The pressure reference remains the same. Add local atmospheric pressure only when an actual reference conversion is needed.
Is standard atmosphere a measurement of air pressure at my location?
No. It is a defined reference of 101,325 pascals. Local weather and elevation affect measured air pressure.
How many psi is one atmosphere?
About 14.7 psi, equal to 101.3 kilopascals or 760 millimeters of mercury.
What is the difference between gauge and absolute pressure?
Gauge pressure uses the local surrounding pressure. Absolute pressure uses a vacuum reference. Add actual ambient pressure to convert.
A rounded standard atmosphere is 14.7 psi. It is an assumption, not every local reading; elevation and weather can change ambient pressure, so match that reference before combining a gauge value with an absolute-pressure equation.
What tire pressure should I use?
Use the value on the label inside the driver's door or in the manual, not the maximum molded on the tire.