Pressure
hPatomH₂O
Convert hectopascals (hPa) to metres of water column (mH₂O).
Factor1 hPa = 0.01019716 mH₂O
Converter
hPa
Accepts numbers or expressions, e.g. 150 + 14.7
Result
mH₂O
Rendered to 6 significant figures.
Formula
Formula
mH₂O = hPa × 0.01019716
Multiply any value in hectopascals by 0.01019716 to obtain the value in metres of water column.
Worked example
Convert 100 hPa to mH₂O.
- 01Start with 100 hPa.
- 02Multiply by the conversion factor: 100 × 0.01019716 = 1.01972 mH₂O.
Result100 hPa = 1.01972 mH₂O
Conversion table
| hPa | mH₂O |
|---|---|
| 1 | 0.010197 |
| 2 | 0.020394 |
| 5 | 0.050986 |
| 10 | 0.10197 |
| 20 | 0.20394 |
| 50 | 0.50986 |
| 100 | 1.0197 |
| 200 | 2.0394 |
| 500 | 5.0986 |
| 1000 | 10.197 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from hPa to mH₂O?
1 hPa equals 0.01019716 mH₂O. To convert, multiply the value in hectopascals by 0.01019716.
How do I convert 1 hPa to mH₂O?
1 hPa = 0.0101972 mH₂O. For any value, multiply by 0.01019716.
How do I convert mH₂O back to hPa?
Divide by the same factor — or equivalently, multiply by 98.0665. So 1 mH₂O = 98.0665 hPa.
When would I need to convert hectopascal to metre of water column?
Pressure conversions between hPa and mH₂O are common when working with mixed-vendor instrumentation, when piping codes use different units to process datasheets, or when converting field readings into SI for hydraulic calculations.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).