What this converter does
This converter turns metres of water head into kilopascals and back instantly. It also covers feet of water, bar and psi — using the density of water at 4 °C. Type a value, pick your units, and read the result as you type.
One metre of water head is 9.807 kPa. Convert pump head to pressure for gauge and pipe ratings. For general pressure units, see the psi to bar converter.
The units it covers
Each unit expresses a pressure or its equivalent liquid column, converting through the kilopascal.
View all units & their values
| Unit | Symbol | Value | Mainly used |
|---|---|---|---|
| Kilopascal | kPa | 1 | SI pressure |
| Metre of water | m H₂O | 9.80665 | Pump & pipe head |
| Foot of water | ft H₂O | 2.98907 | US head |
| Bar | bar | 100 | Process pressure |
| Pound per square inch | psi | 6.89476 | US pressure |
The formula
Each unit has a fixed value in kilopascals, so pressure and head convert through the kPa once (water at 4 °C):
result = value × factor_from ÷ factor_toWhere:
- value = the number you typed, in the “from” unit
- factor_from = the “from” unit’s value in kilopascals
- factor_to = the “to” unit’s value in kilopascals
Worked example
Convert 10 metres of water head to kPa.
1 m H₂O = 9.80665 kPa10 × 9.80665 = 98.07 kPaSo 10 metres of water head is about 98.1 kPa.
The units in this example
A water column height representing pressure — the usual way to state pump head and static lift.
- 1 m H₂O ≈ 9.807 kPa
- 1 m H₂O ≈ 3.281 ft H₂O
- 1 m H₂O ≈ 0.0981 bar
- 1 m H₂O ≈ 1.422 psi
The SI pressure unit used for gauge readings and pipe ratings in water systems.
- 1 kPa ≈ 0.102 m H₂O
- 1 kPa ≈ 0.335 ft H₂O
- 1 kPa = 0.01 bar
- 1 kPa ≈ 0.145 psi