Pressure Converter

Convert pascals, bar, atmospheres, psi, Torr, and conventional mmHg with clear unit choices.

✓ Free to use · Runs in your browser · No sign-up

Enter a value. Your answer appears below.

Choose the unit you have in “From” and the unit you need in “To”. No calculate button needed.

Keep the same reference: changing units does not change gauge pressure into absolute pressure. Torr and conventional mmHg are very close, but not identical.

Numbers only. For example, 12.5 or 1e6 (one million).
Updates automatically
Select this number to copy it manually, or use Copy result below.

Start with a number above, or try the example below.

Example: 1 bar = 100,000 pascals. Results show up to 15 significant digits. Very large or small answers may use e notation: 1e6 means 1,000,000. Numbers are processed only in this browser.

How to use Pressure Converter

  1. Enter the pressure number from the gauge or specification.
  2. Choose its current unit and the desired output unit.
  3. Read the automatic result, keeping the same gauge or absolute reference as the original measurement.

A closer look

Pressure is force per unit area. All choices are compared through pascals: 1 bar = 100,000 Pa and 1 standard atmosphere = 101,325 Pa. PSI means pounds-force per square inch, using standard gravity. Torr is exactly 1/760 of a standard atmosphere. Conventional mmHg uses 133.322387415 Pa, so it is very close to Torr but is not treated as exactly equal.

A practical example

One standard atmosphere equals 101,325 pascals, or 1.01325 bar. The conversion changes units only; it does not add an atmospheric offset to a gauge reading.

A useful tip

A gauge pressure of zero means the surrounding pressure, not a vacuum. Changing psi into bar does not add atmospheric pressure or switch to an absolute reading.

Good questions. Simple answers.

Why are negative pressures accepted?

A negative gauge pressure can describe pressure below the chosen reference. The tool converts the number and does not decide whether it is an absolute or gauge measurement.

Is one atmosphere the same as one bar?

No. One standard atmosphere equals 1.01325 bar. Local atmospheric pressure also varies and is not measured by this tool.

Explore all converters for related tasks and category-specific guidance, or read how Toolzafi handles your data.

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