Conventional inches of mercury to Conventional millimetres of mercury converter
Convert Conventional inches of mercury (inHg (0 °C)) to Conventional millimetres of mercury (mmHg (0 °C)). Calculate a value, check the formula and compare common measurements.
Result for the values shown.
Calculations run in your browser.
What to enter
| Input | Meaning and units |
|---|---|
| Value | Enter value using the definition in the method and example. |
| From | Select the unit or currency in which the entered number is currently expressed. |
| To | Select the unit or currency you need for the answer. |
Understanding your result
The converted value describes the same pressure quantity in the selected target unit. Display rounding does not add precision to the original measurement.
Common mistakes
- Confusing the source and target units, or overlooking a prefix or case-sensitive symbol.
- Expecting a unit conversion to change gauge pressure into absolute pressure.
Check your calculation
- Convert to the target unit and then reverse the direction. Within display rounding, you should recover the original value.
Read the pressure measurement guide · Calculation checks, sources and review limits
How do I convert conventional inches of mercury to conventional millimetres of mercury?
Enter the value in conventional inches of mercury to find the same pressure quantity in conventional millimetres of mercury. The number changes to match the unit; the underlying quantity stays the same. Check the definitions below when a unit has more than one convention.
Common uses
- Interpret pressure specifications in a familiar unit.
- Compare pressure readings using consistent conventions.
How it works
For the displayed direction, 1 inHg (0 °C) equals 25.4 mmHg (0 °C). The engine converts through the shared pressure base quantity. Atmospheres are standard atmospheres. Mercury-column factors use the conventional 0 °C definition; torr is 1/760 of a standard atmosphere. The multiplier is derived from the two centralized unit factors. Keep full precision until the final result; displayed answers use up to 12 significant digits.
Worked example
10 inHg (0 °C) converts to 254 mmHg (0 °C). For the reverse direction, swap the units and enter 254 mmHg (0 °C); the result is approximately 10 inHg (0 °C).
FAQ
How do I convert inHg (0 °C) to mmHg (0 °C)?
mmHg (0 °C) = inHg (0 °C) × 25.4
Which definition is used?
Atmospheres are standard atmospheres. Mercury-column factors use the conventional 0 °C definition; torr is 1/760 of a standard atmosphere.
Common values
Use “Swap units” above for the reverse conversion. Values below are rounded to six significant digits.
| Conventional inches of mercury | Conventional millimetres of mercury |
|---|---|
| 1 | 25.4 |
| 5 | 127 |
| 10 | 254 |
| 20 | 508 |
| 30 | 762 |
| 50 | 1270 |
| 100 | 2540 |