Pressure and vacuum
Convert Pa, hPa, kPa, MPa, bar, mbar, Torr, mmHg, atm and psi—from laboratory measurements to industrial-system parameters.
Engineering tool
Vacuum unit converter
A pressure, volumetric flow and leak-rate converter running directly in your browser. Your data never leaves the device.
Unit calculator
Enter one value
Results update automatically when the number or input unit changes.
—Pa
—hPa
—kPa
—MPa
—bar
—mbar
—Torr
—mmHg
—atm
—psi
—Pa·m³/s
—mbar·l/s
—Torr·l/s
—atm·cm³/s
—atm·ft³/year
—m³/s
—m³/h
—l/s
—l/min
—cm³/s
—ft³/year
—CFM
Conversion scope
Vacuum unit converter for engineers
One tool covers three quantities used in vacuum-system design, measurement and diagnostics. Results are calculated locally and displayed simultaneously in every available unit.
Leak rate and gas throughput
Compare Pa·m³/s, mbar·L/s, Torr·L/s, atm·cm³/s and atm·ft³/year used in leak testing and equipment specifications.
Volumetric flow
Convert m³/s, m³/h, L/s, L/min, cm³/s, ft³/year and CFM when sizing pumps, pipework and gas systems.
How to use it
Convert units in three quick steps
The calculator accepts decimal and scientific notation. You can use a decimal point or comma as the decimal separator.
Choose the quantity
Open the pressure, leak-rate or volumetric-flow tab.
Enter a value and unit
Select the source unit and enter the measured or catalogue value.
Read all results
Compare the equivalent values and set the number of significant digits to match the accuracy of your data.
Common questions
Vacuum, leak-rate and flow units
Are Torr and mmHg exactly the same?
They are nearly equal but have different definitions. One Torr is exactly 1/760 of a standard atmosphere, while mmHg is based on the pressure of a mercury column. The converter preserves this small difference.
How does leak rate differ from volumetric flow?
Leak rate describes gas throughput as pressure multiplied by volume per time, for example mbar·L/s. Volumetric flow describes volume per time, for example L/s, so the quantities are not interchangeable without a pressure value.
How many significant digits should I use?
A result should not imply greater accuracy than the input data. Two or three significant digits are usually enough for quick estimates; use more only when the source data supports that precision.