Pressure
inHgtoftH₂O
Convert inches of mercury (0 °C) (inHg) to feet of water column (4 °C) (ftH₂O).
Factor1 inHg = 1.132925 ftH₂O
Converter
inHg
Accepts numbers or expressions, e.g. 150 + 14.7
Result
ftH₂O
Rendered to 6 significant figures.
Formula
Formula
ftH₂O = inHg × 1.132925
Multiply any value in inches of mercury (0 °C) by 1.132925 to obtain the value in feet of water column (4 °C).
Worked example
Convert 30 inHg to ftH₂O.
- 01Start with 30 inHg.
- 02Multiply by the conversion factor: 30 × 1.132925 = 33.9878 ftH₂O.
Result30 inHg = 33.9878 ftH₂O
Conversion table
| inHg | ftH₂O |
|---|---|
| 1 | 1.1329 |
| 2 | 2.2659 |
| 5 | 5.6646 |
| 10 | 11.329 |
| 20 | 22.659 |
| 50 | 56.646 |
| 100 | 113.29 |
| 200 | 226.59 |
| 500 | 566.46 |
| 1000 | 1132.9 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from inHg to ftH₂O?
1 inHg equals 1.132925 ftH₂O. To convert, multiply the value in inches of mercury (0 °C) by 1.132925.
How do I convert 1 inHg to ftH₂O?
1 inHg = 1.13293 ftH₂O. For any value, multiply by 1.132925.
How do I convert ftH₂O back to inHg?
Divide by the same factor — or equivalently, multiply by 0.8826709. So 1 ftH₂O = 0.882671 inHg.
When would I need to convert inch of mercury (0 °C) to foot of water column (4 °C)?
Pressure conversions between inHg and ftH₂O 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).