Conventional inches of mercury to atmospheres converter
Convert Conventional inches of mercury (inHg (0 °C)) to atmospheres (atm). 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 atmospheres?
Enter the value in conventional inches of mercury to find the same pressure quantity in atmospheres. 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 0.033421057393 atm. 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 0.33421057393 atm. For the reverse direction, swap the units and enter 0.33421057393 atm; the result is approximately 10 inHg (0 °C).
FAQ
How do I convert inHg (0 °C) to atm?
atm = inHg (0 °C) × 0.033421057393
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 | atmospheres |
|---|---|
| 1 | 0.0334211 |
| 5 | 0.167105 |
| 10 | 0.334211 |
| 20 | 0.668421 |
| 30 | 1.00263 |
| 50 | 1.67105 |
| 100 | 3.34211 |