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Featured pressure sensor products
Pressure Sensors for Data Logging with a Computer - Easily log and analyze pressure data on your PC. These digital sensors connect via serial interfaces and come with software for preset interval logging of fluids and gases.
0-5 Volts Output Pressure Transducers - Industrial grade 0-5Vdc pressure transducers. These sensors provide a stable, amplified analog output ideal for automation, hydraulics, and process control.
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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
Pressure Gauges with Integral Data Logger - Digital pressure gauges combined with a programmable data logger for recording pneumatic or hydraulic pressures at set time periods.
Clean room monitoring system to measure pressure, humidity & temperature in 4 individual rooms - A complete clean room measurement system for 4 separate rooms, each with its own room pressure, humidity and air temperature indicator, and a central monitoring unit for clean room corridor or control room.
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
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Intrinsically Safe Pressure Data Loggers - Select from our range of battery powered, intrinsically safe pressure data loggers for hazardous zones. Features include configurable logging, event triggers, and data analysis.
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
Balancing air pressure in marine engine rooms with a low range dp sensor - Low-range bidirectional differential pressure sensor helps maintain the critical air balance in a sealed vessel engine room, ensuring optimal engine combustion and ventilation performance.
Heating appliance chimney draft and barometric pressure testing using differential and absolute sensors - Very low, bi-directional chimney draft pressure and barometric pressure sensor for testing preformance of wood stoves in a research environment.
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
PGS40 Mid Pressure Calibration Hand Pump - PGS40 pneumatic hand pump for applying test and calibration pressures with precision from -0.96 up to 40 bar gauge. 
Vacuum Pressure Transducers - Explore vacuum pressure transducers with voltage outputs (0-5V, 0-10V, 0.5-4.5V). Select absolute or gauge references for partial/full vacuum ranges.
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
Air Pressure Calibrators - Ensure the accuracy of your pneumatic pressure instruments with our range of pressure calibrators, hand pumps, and test gauges.- PGS40 Mid Pressure Calibration Hand Pump - PGS40 pneumatic hand pump for applying test and calibration pressures with precision from -0.96 up to 40 bar gauge.