Pressure Converter

What Is the Pressure Converter?

The Pressure Converter converts a pressure value between the units used in everyday life, science, and engineering: pascals (Pa), kilopascals (kPa), pounds per square inch (PSI), atmospheres (atm), bar, millimetres of mercury (mmHg), and torr (Torr). Pressure is force per unit area, and the SI unit is the pascal: 1 Pa = 1 newton per square metre.

How to Use the Pressure Converter

1. Enter the pressure value in pascals (Pa) in the Value box. If your reading is in another unit, convert it to pascals first: 1 bar = 100,000 Pa, 1 atm = 101,325 Pa, and 1 PSI = 6,894.76 Pa.
2. Use the From and To dropdowns to note the units you are working with, and use Swap to reverse them.
3. Click Process.
4. Read the result, which lists the equivalent pressure in PSI, atm, and mmHg.
5. Use Copy or Download to save the result.

Worked Example

Enter 2 and click Process. The result reads: 2 Pa = 0.00029008 PSI, 2 Pa = 0.000019738 atm, and 2 Pa = 0.015001 mmHg. To convert a bar reading, first multiply by 100,000: 2 bar = 200,000 Pa, which is about 29.01 PSI (200,000 x 0.00014504, the tool’s PSI-per-pascal factor).

Limitations

• The result list is calculated from the base unit, the pascal. Enter the value in Pa, or convert it to Pa first using the factors above.
• The From and To dropdowns do not change the calculation. The result is computed from the number you entered, treated as pascals.
• Results are rounded, so very small pressures may display with limited precision. Keep extra digits for laboratory work.
• The tool converts pressure units only. It does not account for temperature, altitude, or whether a reading is gauge or absolute pressure.
• Gauge readings, such as tyre pressure, exclude atmospheric pressure. Add about 101,325 Pa (14.70 PSI) if you need absolute pressure.

Frequently Asked Questions

How many pascals are in 1 bar?

Exactly 100,000 Pa. So 2.5 bar = 250,000 Pa.

How many PSI are in 1 atmosphere?

1 atm = 101,325 Pa, and 1 PSI = 6,894.76 Pa, so 1 atm = 14.6959 PSI.

What is mmHg?

A millimetre of mercury is the pressure exerted by a 1 mm column of mercury: 1 mmHg = 133.322 Pa. It is still used for blood pressure readings, such as 120/80 mmHg.

Can I convert gauge pressure?

Yes, as a number. The tool converts the value you enter. Gauge readings exclude atmospheric pressure, so add about 101,325 Pa (14.70 PSI) if you need the absolute pressure.