Click save settings to reload page with unique web page address for bookmarking and sharing the current tool settings, or click swap units to quickly exchange the selected units
Featured pressure sensor products
DPS Low Differential Pressure Transmitter - Ultra low differential pressure transmitter for HVAC applications with 4-20mA current loop or amplified voltage output signal in pressure ranges from 0.1 mb up to 1 bar differential. 
ATEX approved negative 10 mbar vacuum pressure transmitter - ATEX certified intrinsically safe pressure transmitter for measuring from 0 to minus 10 millibar gauge vacuum pressure.
Related Tools
- Force and area to pressure converter
- Pressure and area to force converter
- Pressure to liquid level calculator
- Liquid level to pressure calculator
User Guide
This converter and dynamic conversion scale will calculate the equivalent pressure value from one pressure measurement unit to another and generate a conversion table based on the selected units.
- Enter the value you want to convert in the upper input box.
- Select the corresponding units from the upper shortcut buttons or pull down options.
- Select the units to convert to, from the lower shortcut buttons or pull down options.
- The conversion will show in the lower answer box.
You can also copy and paste values into this converter, after pasting a value, click or touch the input box to convert the value.
Conversion Guide
Convert pressure units with the pressure unit converting tool, look up a conversion from the tables, identify a pressure unit and its group association with other pressure units, or find the relevant pressure conversion factor in pascals.
Conversion Tables
Choose a look up table for a specific pressure conversion application.
- Tyre pressure conversion for cars, trucks, cycles, motorbikes or aircraft
- Barometric conversion for mbar, hPa, psi, inHg, mmHg & Torr
- Vacuum conversion for % vac, mbar, hPa, psi, inHg, mmHg & Torr
- Altitude to pressure conversion from feet or metres to mbar, psi, mmHg & inHg
- I/P & P/I conversion for current and pneumatic signal control instrumentation
- E/P & P/E conversion for voltage and pneumatic signal control instrumentation
Featured pressure gauge products
Low Range Pressure Gauges - Source reliable digital low pressure gauges offering high resolution, multi-unit display, min/max capture, and zero function for critical low-pressure applications.
10 bar g steam pressure transmitter, indicator and PNP switch - Steam pressure transmitter with LED display indicator for measuring 0 to 10 bars with in-built temperature reducer
Conversion Factors
The following list shows each pressure unit and its equivalent value converted into pascals (Pa). The pascal is the SI unit for measuring pressure.
Unique Conversion Factors
These units have an internationally agreed definition for the conversion factor, some have an exact value with very few digits, while others have a lot of digits and may vary very slightly between reference sources, depending on the level of precision used when calculating the values.
| Symbol | Name | Pascals Value |
|---|---|---|
| bar | Bar | 100,000 |
| psi, pfsi, lb/in², lbf/in² | Pounds Force Per Square Inch | 6894.75729316836 … |
| mbar, mb, mbr | Millibar | 100 |
| N/m² | Newton Per Square Metre | 1 |
| Pa | Pascal | 1 |
| hPa | Hectopascal | 100 |
| kPa | Kilopascal | 1,000 |
| MPa | Megapascal | 1,000,000 |
| kg/cm², kgf/cm² | Kilogram Per Square Centimetre | 98,066.5 |
| Torr | Torr | 133.322368421053 … |
| mTorr | Millitorr | 0.133322368421053 … |
| atm | Standard Atmosphere | 101,325 |
| at | Technical Atmosphere | 98,066.5 |
| dyn/cm², dyne/cm² | Dyne Per Square Centimetre | 0.1 |
| oz/in², ozf/in² | Ounce Per Square Inch | 430.922330823023 … |
| tsi, tfsi (uk, long) | Ton Per Square Inch (uk, long) | 15,444,256.3366971 … |
| tsi, tfsi (usa, short) | Ton Per Square Inch (usa, short) | 13,789,514.5863367 … |
| tsf, tfsf (usa, short) | Ton Per Square Foot (usa, short) | 95,760.5179606717 … |
| psf, pfsf | Pounds Force Per Square Foot | 47.8802589803358 … |
| g/cm², gf/cm² | Gram Per Square Centimetre | 98.0665 |
N.B. Numbers which include […] on the end are rounded.
Manometric Conversion Factors
The following units are known as manometric pressure units and are derived from the pressure exerted by a column of liquid under the acceleration of earth’s gravity. Each manometric pressure unit is shown with its equivalent value converted into pascals (Pa). The pascal is the SI unit for measuring pressure.
Since the pressure of the fluid column can vary with changes in liquid density and local gravity it is important to quantify these factors when using these units. The physical assumptions that these conversions factors are based can be found at the bottom of this section.
The use of manometric units is discouraged by national standard organisations because they do not precisely represent the true pressure and there are differing conventions used for the temperature and density of the liquid which can lead to variation in accuracy.
| Symbol | Name | Pascals Value |
|---|---|---|
| mmH2O, mmWG, mmWC | Millimetres of Water | 9.80665 |
| cmH2O, cmWG, cmWC | Centimetres of Water | 98.0665 |
| mH2O, mWG, mWC | Metres of Water | 9,806.65 |
| inH2O, inWG, inWC | Inches of Water | 249.08891 |
| ftH2O, ftWG, ftWC | Feet of Water | 2,989.06692 |
| mmHg | Millimetres of Mercury | 133.322387415 |
| cmHg | Centimetres of Mercury | 1,333.22387415 |
| inHg | Inches of Mercury | 3,386.388640341 |
| µHg, µmHg | Microns of Mercury | 0.133322387415 |
The above manometric pressure units assume the following in their derivation and although they are not physical constants they have been accepted as popular conventions and are used universally:
- Standard acceleration due to gravity of 9.80665 m/s²
- Density of pure water at 4 deg C is 1000 kg/m³
- Density of mercury at 0 deg C is 13,595.1 kg/m³
Featured pressure data logger products
Submersible IP68 Water Pressure Data Logger - P-TRITON-P logger is completely waterproof for flood protection and battery powered with a typical battery life of 10 years.
Air Pressure Data-Loggers - Air pressure data loggers are essential tools for monitoring and recording air pressure in various industrial and research settings.
Pascal SI Metric Prefix Pressure Units
These pressure units belong to the SI measurement system where the pascal is derived from the SI units by the following formulas: 1 kg·m-1·s-2 ⇒ 1 N·m-2 ⇒ 1 Pa.
- quectopascal (qPa) – 1 x 10-30 Pa
- rontopascal (rPa) – 1 x 10-27 Pa
- yoctopascal (yPa) – 1 x 10-24 Pa
- zeptopascal (zPa) – 1 x 10-21 Pa
- attopascal (aPa) – 1 x 10-18 Pa
- femtopascal (fPa) – 1 x 10-15 Pa
- picopascal (pPa) – 1 x 10-12 Pa
- nanopascal (nPa) – 1 x 10-9 Pa
- micropascal (µPa) – 0.000001 Pa
- millipascal (mPa) – 0.001 Pa
- centipascal (cPa) – 0.01 Pa
- decipascal (dPa) – 0.1 Pa
- pascal (Pa) – 1 Pa
- decapascal (daPa) – 10 Pa
- hectopascal (hPa) – 100 Pa
- kilopascal (kPa) – 1,000 Pa
- megapascal (MPa) – 1,000,000 Pa
- gigapascal (GPa) – 1 x 10+9 Pa
- terapascal (TPa) – 1 x 10+12 Pa
- petapascal (PPa) – 1 x 10+15 Pa
- exapascal (EPa) – 1 x 10+18 Pa
- zettapascal (ZPa) – 1 x 10+21 Pa
- yottapascal (YPa) – 1 x 10+24 Pa
- ronnapascal (RPa) – 1 x 10+27 Pa
- quettapascal (QPa) – 1 x 10+30 Pa
Featured pascal pressure measurement products
- 0 to 9 pascals range pressure gauge - Low Pascal range pressure gauge for measuring from 0 to 9 pascals and provide a digital readout of the pressure readings?
Monitoring data center positive pressure with a low-range differential transducer - Low-range differential pressure transducer for verifying and monitoring critical positive air pressure between a data center equipment room and adjacent areas, ensuring compliance with required ≥5 Pa and ≥10 Pa thresholds.
Bar Metric Prefix Pressure Units
These pressure units which belong to the metric unit system where the bar is defined as being exactly equal to 100,000 pascals.
- quectobar (qbar) – 1 x 10-25 Pa
- rontobar (rbar) – 1 x 10-22 Pa
- yoctobar (ybar) – 1 x 10-19 Pa
- zeptobar (zbar) – 1 x 10-16 Pa
- attobar (abar) – 1 x 10-13 Pa
- femtobar (fbar) – 1 x 10-10 Pa
- picobar (pbar) – 1 x 10-7 Pa
- nanobar (nbar) – 1 x 10-4 Pa
- microbar (µbar) – 0.1 Pa
- millibar (mbar) – 100 Pa
- centibar (cbar) – 1,000 Pa
- decibar (dbar) – 10,000 Pa
- bar (bar) – 100,000 Pa
- decabar (dabar) – 1,000,000 Pa
- hectobar (hbar) – 10,000,000 Pa
- kilobar (kbar) – 1 x 10+8 Pa
- megabar (Mbar) – 1 x 10+11 Pa
- gigabar (Gbar) – 1 x 10+14 Pa
- terabar (Tbar) – 1 x 10+17 Pa
- petabar (Pbar) – 1 x 10+20 Pa
- exabar (Ebar) – 1 x 10+23 Pa
- zettabar (Zbar) – 1 x 10+26 Pa
- yottabar (Ybar) – 1 x 10+29 Pa
- ronnabar (Rbar) – 1 x 10+32 Pa
- quettabar (Qbar) – 1 x 10+35 Pa
Torr Metric Prefix Pressure Units
These pressure units are defined as being exactly equal to 1/760 of one standard atmosphere (101,325 Pa), which can be easily incorporated into calculations simply as 101325/760 Pa which is approximately equal to 133.322 pascals.
- quectotorr (qTorr) – 1.33322368421053 x 10-28 Pa
- rontotorr (rTorr) – 1.33322368421053 x 10-25 Pa
- yoctotorr (yTorr) – 1.33322368421053 x 10-22 Pa
- zeptotorr (zTorr) – 1.33322368421053 x 10-19 Pa
- attotorr (aTorr) – 1.33322368421053 x 10-16 Pa
- femtotorr (fTorr) – 1.33322368421053 x 10-13 Pa
- picotorr (pTorr) – 1.33322368421053 x 10-10 Pa
- nanotorr (nTorr) – 1.33322368421053 x 10-7 Pa
- microtorr (µTorr) – 1.33322368421053 x 10-4 Pa
- millitorr (mTorr) – 0.133322368421053 Pa
- centitorr (cTorr) – 1.33322368421053 Pa
- decitorr (dTorr) – 13.3322368421053 Pa
- torr (Torr) – 133.322368421053… Pa
- decatorr (daTorr) – 1,333.22368421053 Pa
- hectotorr (hTorr) – 13,332.2368421053 Pa
- kilotorr (kTorr) – 1.33322368421053 x 10+5 Pa
- megatorr (MTorr) – 1.33322368421053 x 10+8 Pa
- gigatorr (GTorr) – 1.33322368421053 x 10+11 Pa
- teratorr (TTorr) – 1.33322368421053 x 10+14 Pa
- petatorr (PTorr) – 1.33322368421053 x 10+17 Pa
- exatorr (ETorr) – 1.33322368421053 x 10+20 Pa
- zettatorr (ZTorr) – 1.33322368421053 x 10+23 Pa
- yottatorr (YTorr) – 1.33322368421053 x 10+26 Pa
- ronnatorr (RTorr) – 1.33322368421053 x 10+29 Pa
- quettatorr (QTorr) – 1.33322368421053 x 10+32 Pa
Featured vacuum pressure measurement products
DS200 Combined Pressure Switch, Gauge and Sensor - Three in one electronic pressure switch, digital pressure gauge and pressure sensor with pressure ranges from 100 mbar up to 600 bar (1.5 to 9000 psi).
DPS200 HVAC Differential Pressure Transmitter - Differential air pressure sensor with a 10 volt or a 4-20mA output for building ventilation applications. Ranges from 0 to 6 mbar up to 0 to 1000 mbar.
Unit Groups
Many units have a similar application or derivation, the use of each varies depending on country, industry and pressure value
Units derived from ‘pascal’ the SI unit for pressure
Force related pressure units
- N/m²
- dyn/cm², dyne/cm², dynes/cm², d/cm²
- kg/cm², kgf/cm²
- g/cm², gf/cm²
- psi, pfsi, lb/in², lbf/in²
- oz/in², ozf/in²
- tsi (uk, long), tfsi (uk, long)
- tsi (usa, short), tfsi (usa, short)
- tsf (usa, short), tfsf (usa, short)
- psf, pfsf
Water related pressure units
- mm H2O, mm WG, mm WC
- cm H2O, cm WG, cm WC
- m H2O, m WG, m WC
- in H2O, in WG, in WC, “H2O, “WG, “WC
- ft H2O, ft WG, ft WC, ‘H2O, ‘WG, ‘WC
Mercury related pressure units
Atmosphere pressure units
Featured pressure calibration products
Low Pressure Calibrators - Explore low pressure calibrators featuring fine volume adjustment pumps and high-accuracy indicators for precise calibration in Pa, mbar, or "WC ranges. Ideal for sensitive instruments.
Vacuum Range Calibration Equipment - Maintain the accuracy of your vacuum sensors, gauges, and switches with high-quality vacuum calibration equipment.