1 millimeter of water [mmH2O] = 0.002896 inch of mercury [inHg]
Example: 1 millimeter of water [mmH2O] equals 0.002896 inch of mercury [inHg].
Examples
1 millimeter of water [mmH2O] = 0.002896 inch of mercury [inHg]
2 millimeter of water [mmH2O] = 0.005792 inch of mercury [inHg]
5 millimeter of water [mmH2O] = 0.01448 inch of mercury [inHg]
10 millimeter of water [mmH2O] = 0.028959 inch of mercury [inHg]
20 millimeter of water [mmH2O] = 0.057918 inch of mercury [inHg]
25 millimeter of water [mmH2O] = 0.072398 inch of mercury [inHg]
Practical Uses for millimeter water to inch mercury
tire inflationcompressors and pumpsHVAC and plumbingengineering specifications
Sources and Accuracy
Pressure conversions use pascal as the reference unit and include common engineering, weather, tire, and laboratory pressure units.
Displayed results are rounded for readability. The calculator keeps enough precision for everyday use and switches to scientific notation for very large or very small values. Last reviewed: 2026-08-14.
About These Units
millimeter of water [mmH2O]
Definition
The millimeter of water (mmH2O) is a pressure unit used to express measurements in this converter.
History
This unit is included because it appears in practical measurement systems, technical references, product specifications, or everyday conversion needs.
Current use
Use millimeter of water when comparing pressure values, checking specifications, converting between systems, or preparing quick estimates.
inch of mercury [inHg]
Definition
The inch of mercury (inHg) is a pressure unit used to express measurements in this converter.
History
This unit is included because it appears in practical measurement systems, technical references, product specifications, or everyday conversion needs.
Current use
Use inch of mercury when comparing pressure values, checking specifications, converting between systems, or preparing quick estimates.
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How to Convert
Enter the value in the “From value” field.
Confirm the source unit is millimeter of water [mmH2O].
Confirm the target unit is inch of mercury [inHg].
Read the instant result and formula.
Where This Conversion Is Used
tire inflationcompressors and pumpsHVAC and plumbingengineering specifications