1. Identify the reference
Distinguish absolute pressure from gauge pressure and pressure drop across a filter.
Engineering Tool · Pressure & Differential Pressure
Pressure Unit Converter
Convert pressure or pressure difference among Pa, kPa, MPa, bar, mbar, psi, atm and Torr for filtration system specifications.
Reference basis: this tool converts the numerical unit only. Choose absolute, gauge or differential pressure before entering the value; it does not add atmospheric pressure.
Enter pressure
Keep the same pressure reference on the input and output.
Gauge and differential values can be negative. Absolute pressure cannot be negative.
Converted values
All results are pressure differences.
Pascal100,000 Pa
Kilopascal100 kPa
Megapascal0.1 MPa
Bar1 bar
Millibar1,000 mbar
Pounds per square inch14.5038 psi
Standard atmosphere0.986923 atm
Torr750.062 Torr
Conversion basis
All inputs convert to pascals first. 1 bar = 100,000 Pa; 1 atm = 101,325 Pa; 1 psi ≈ 6,894.757293 Pa.
Displayed values are rounded; calculations retain the unrounded input value.
How to use the converter
2. Enter the value and unit
Select the supplied pressure unit. The values update as you type or change the dropdown.
3. Keep the reference
Conversions keep the same reference; a gauge-to-absolute transformation needs an atmospheric pressure input.
Frequently asked questions
Is 1 bar the same as 1 atmosphere?
No. 1 bar is exactly 100,000 Pa; 1 standard atmosphere is exactly 101,325 Pa.
Does this convert gauge pressure to absolute pressure?
No. The numeric unit changes while the pressure reference stays the same. To convert gauge to absolute, add the relevant local atmospheric pressure separately.
Can I enter a negative value?
A negative gauge pressure or signed pressure difference is allowed. A negative absolute pressure is not physically valid and is rejected.
Which pressure should I use for a filter pressure drop?
Use the difference between the inlet and outlet measurement points at the same operating condition. This converter does not calculate pressure loss from flow.
Need filtration pressure-drop analysis?
Convert units here, then select a physical model in the existing engineering workbench.
Open Flow & Pressure Drop CalculatorEngineering note: Unit conversion alone does not establish a filter rating, allowable differential pressure or operating pressure.
