Centimeters of Mercury is a small pressure unit which represents the pressure pushing down due to gravity of any volume of liquid mercury which is 1cm high. 1 centimeter of mercury at zero degrees Celsius equals 1333.22 pascals.

The use of cmHg is not as common as mmHg, it is mainly used in applications for measuring pressures of vacuum pumps, pneumatic systems, automotive engine inlet manifold pressures and blood pressure.

For more background on how mercury is used to measure pressure please vist our mmHg page

Please use the table below to determine the value of 1 Centimeter of Mercury in different pressure units.

For the reverse conversion factor into cmHg please click on the appropriate pressure unit link below.

To calculate cmHg pressure conversions online please go to our pressure converter page.

View the calculation for deriving cmHg from SI units or a list of different ways to identify the cmHg pressure unit.

## Conversion Factors

- 0.0133322 bar
- 0.193368 psi
- 13.3322 mbar
- 1333.22 N/m²
- 1333.22 Pa
- 13.3322 hPa
- 1.33322 kPa
- 0.00133322 MPa
- 0.0135951 kg/cm²
- 135.951 mmH2O 4°C (39.2°F)
- 13.5951 cmH2O 4°C (39.2°F)
- 0.135951 mH2O 4°C (39.2°F)
- 5.35240 inH2O 4°C (39.2°F)
- 0.446033 ftH2O 4°C (39.2°F)
- 10 mmHg 0°C (32°F)
- 1 cmHg 0°C (32°F)
- 0.393701 inHg 0°C (32°F)
- 10.00000 Torr
- 10000.00 mTorr
- 0.0131579 atm
- 0.0135951 at
- 13332.2 dyn/cm²
- 3.09388 oz/in²
- 10000 µHg 0°C (32°F)
- 0.0000863249 tsi (uk, long)
- 0.0000966839 tsi (usa, short)
- 0.0139225 tsf (usa, short)
- 27.8450 psf
- 13.5951 g/cm²

*Please note that the conversion factors above are accurate to 6 significant figures.*

## Derivation

The calculation below shows how the pressure unit centimetres of mercury (cmHg) is derived from SI Units.

#### Formula

- Pressure = Force / Area
- Force = Mass x Acceleration
- Mass = Density x Volume
- Volume = Area x Height
- Acceleration = Distance / (Time x Time)

#### SI Units

- Mass: kilogram (kg)
- Distance: metre (m)
- Time: second (s)
- Force: newton (N)
- Pressure: pascal (Pa)

#### Input Values

- Density = Mercury Density at 0degC = 13595.1 kg/m³
- Area = 1 m²
- Height = 1 cm = 0.01 m
- Acceleration = Standard Gravity = 9.80665 m/s²

#### Calculation

- 1 cmHg Mass = 13595.1 kg/m³ x 1 m² x 0.01 m = 135.951 kg
- 1 cmHg Force = 135.951 kg x 9.80665 m/s² = 1333.223874 N
- 1 cmHg Pressure = 1333.223874 N / 1 m² = 1333.223874 Pa

## Alternate Descriptions

These are the different versions used for identifying cmHg that you may find elsewhere.

- centimetres of mercury
- centimeters of mercury
- centimetres of mercury column
- centimeters of mercury column
- cmHg
- cm Hg