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Pressure Converter

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Convert pressure between PSI, bar, kilopascals, atmospheres, and mmHg instantly.

Pressure Converter

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Converted value
2.068 bar

The formula

Result = Value x (kPa per "From" unit) / (kPa per "To" unit)
Example

30 PSI converts to about 2.068 bar, or 206.84 kPa, or 2.041 atmospheres.

Step-by-step guide

  1. Enter the value you want to convert.
  2. Choose the "from" and "to" units.
  3. Read the converted result.

Where each unit is commonly used

PSI (pounds per square inch) is standard in the US for tire pressure, plumbing, and compressed air. Bar and kPa are common internationally and in scientific contexts - 1 bar is very close to standard atmospheric pressure, which makes it an intuitive reference point. Atmospheres (atm) express pressure directly as a multiple of sea-level air pressure. mmHg (millimeters of mercury, also called torr) is traditional in medical blood pressure readings and some vacuum measurements.

Common mistakes

Confusing gauge pressure (relative to atmospheric, what a tire gauge reads) with absolute pressure (relative to a true vacuum) - the two differ by about 14.7 PSI at sea level, and mixing them up leads to real calculation errors in engineering contexts.
Mixing up kPa and MPa - a factor-of-1,000 error is easy to make when a spec sheet uses megapascals instead of kilopascals.

Frequently asked questions

Is this gauge pressure or absolute pressure?

This converter treats your input as a direct value in the selected unit without adjusting for the gauge/absolute distinction - if your source measurement is specifically gauge or absolute pressure, keep that same convention consistent through your calculation.

Why is atmospheric pressure sometimes given as 14.7 and other times as 1?

Both describe the same standard sea-level pressure, just in different units - 14.7 is in PSI, while 1 is in atmospheres (atm), which is defined as exactly that reference pressure.

What's a typical tire pressure in different units?

A common passenger car tire pressure of around 32 PSI converts to roughly 2.2 bar or 221 kPa - always check your specific vehicle's recommended pressure rather than relying on a general figure.

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