Hectopascal is a 100x multiple of the pascal, which is the SI unit for pressure. The hectopascal is the international unit for measuring atmospheric or barometric pressure. 1 hectopascal equals 100 pascals.

Due to its low value the hectopascal is ideal for use as a measure of atmospheric pressure and other low gas pressures such as air flow differentials in air conditioning systems or wind tunnels.

One hectopascal is exactly equal to one millibar and although the scientific community has officially adopted the hectopascal in preference to the millibar, the millibar is still used extensively throughout the world due to the proliferation of its use historically.

You can convert a reading in hectopascals into different engineering units by multiplying it by the appropriate conversion factor in the list below.

Alternatively you can let the pressure unit converter do the calculation for you.

## hPa Pressure Conversion Factors

- 0.001 bar
- 0.0145038 psi
- 1 mbar
- 100 N/m²
- 100 Pa
- 1 hPa
- 0.1 kPa
- 0.0001 MPa
- 0.00101972 kg/cm²
- 10.1972 mmH2O 4°C (39.2°F)
- 1.01972 cmH2O 4°C (39.2°F)
- 0.0101972 mH2O 4°C (39.2°F)
- 0.401463 inH2O 4°C (39.2°F)
- 0.0334553 ftH2O 4°C (39.2°F)
- 0.750062 mmHg 0°C (32°F)
- 0.0750062 cmHg 0°C (32°F)
- 0.0295300 inHg 0°C (32°F)
- 0.750062 Torr
- 750.062 mTorr
- 0.000986923 atm
- 0.00101972 at
- 1000 dyn/cm²
- 0.232060 oz/in²
- 750.062 µHg 0°C (32°F)
- 0.00000647490 tsi (uk, long)
- 0.00000725189 tsi (usa, short)
- 0.00104427 tsf (usa, short)
- 2.08854 psf
- 1.01972 g/cm²

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

## hPa Help

### hPa to mb units

*What is the conversion from hpa to mbs, e.g. 1018 hPa to mbs?*

The hPa (hectopascal) unit has exactly the same value as mb (millibar) unit, so the conversion is one to one, 1018 hPa = 1018 mbs exactly.

### Barometric pressure

*What does hPa mean in relation to barometric pressure?*

hPa is the abbreviated name for hectopascal (100 x 1 pascal) pressure units which are exactly equal to millibar pressure unit (mb or mbar). The hectopascal or millibar is the preferred unit for recording and predicting barometric or atmospheric pressure in European and many other countries weather reports. Despite the official directive by the World Meteorological Organisation in 1986 to phase out the use of the millibar in favour of the hectopascal, it is still widely used.

## Measurement Unit Related Terms

More pages related to measurement unit technical terms.

- at – Technical Atmosphere Pressure Unit
- atm – Standard Atmosphere Pressure Unit
- bar Pressure Unit
- cmH2O – Centimetres of Water Column at 4 deg C Pressure Unit
- cmHg – Centimetres of Mercury at 0 deg C Pressure Unit
- daPa – Dekapascal Pressure Unit
- dyn/cm2 – Dyne per Square Centimetre Pressure Unit
- ftH2O – Feet of Water Column at 4 deg C Pressure Unit
- g – Acceleration due to Gravity
- g/cm² – Grams per Square Centimetre Pressure Unit
- inH2O – Inches of Water Column at 4 deg C Pressure Unit
- inHg – Inches of Mercury at 0 degrees C Pressure Unit
- kg/cm² – Kilogram per Square Centimetre Pressure Unit
- kg/mm² – Kilogram per Square Millimetre Pressure Unit
- kPa – Kilopascal Pressure Unit
- ksi – Kilopounds per Square Inch Pressure Unit
- mbar – Millibar Pressure Unit
- mH2O – Metres of Water Gauge at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- mmHg – Millimetres of Mercury at 0 deg C Pressure Unit
- MPa – Megapascal Pressure Unit
- mPa – Millipascal Pressure Unit
- mTorr – Millitorr Pressure Unit
- N/cm² – Newton per Square Centimetre Pressure Unit
- N/m2 – Newton per Square Metre Pressure Unit
- N/mm² – Newton per Square Millimetre Pressure Unit
- oz/in² – Ounce per Square Inch Pressure Unit
- Pa – Pascal Pressure Unit
- Pressure
- Pressure Units
- psf – Pounds per Square Foot Pressure Unit
- psi – Pounds per Square Inch Pressure Unit
- Specific Gravity
- Torr – Torr Pressure Unit
- tsf – Tons per Square Foot (USA, Short) Pressure Unit
- tsi – Tons per Square Inch (UK, Long) Pressure Unit
- tsi – Tons per Square Inch (USA, Short) Pressure Unit
- Water Density
- µHg – Micron of Mercury at 0 deg C Pressure Unit