Inches of mercury Converter
Convert Inches of mercury (inHg) to any other pressure unit. The table below gives the exact figure for each unit, and every conversion is worked from the same engine as the converter.
What inches of mercury convert to
One inHg in every other pressure unit.
| Unit | 1 inHg | Reverse |
|---|---|---|
| Pascals | 3,386.389 Pa | 2.953e-4 inHg |
| Kilopascals | 3.386389 kPa | 0.2953 inHg |
| Megapascals | 0.003386 MPa | 295.299802 inHg |
| Bar | 0.033864 bar | 29.52998 inHg |
| Millibar | 33.86389 mbar | 0.02953 inHg |
| Atmospheres | 0.033421 atm | 29.921252 inHg |
| Pounds per square inch | 0.491154 psi | 2.03602 inHg |
| Millimeters of mercury | 25.400003 mmHg | 0.03937 inHg |
Multiply a inches of mercury figure by the figure in the second column to get the unit in the first, or multiply by the third column to go the other way.
Inches of mercury conversion reference
Inches of mercury to Pascals
One inches of mercury is 3,386.389 pascals, and one pascals is 2.953e-4 inches of mercury.
The pascal is the SI unit of pressure: one newton per square meter. It is used in science and engineering, usually as kilopascals or megapascals.
- 1 inHg= 3,386.389 Pa
- 2 inHg= 6,772.778 Pa
- 5 inHg= 16,931.945 Pa
Inches of mercury to Kilopascals
One inches of mercury is 3.386389 kilopascals, and one kilopascals is 0.2953 inches of mercury.
A kilopascal is 1,000 pascals. It is the unit for tyre pressure in metric countries, and is used for gas and weather pressures.
- 1 inHg= 3.386389 kPa
- 2 inHg= 6.772778 kPa
- 5 inHg= 16.931945 kPa
Inches of mercury to Megapascals
One inches of mercury is 0.003386 megapascals, and one megapascals is 295.299802 inches of mercury.
A megapascal is 1,000 kilopascals, or one million pascals. It is used for concrete strength, where structural concrete is typically specified between 20 and 40 MPa.
- 1 inHg= 0.003386 MPa
- 2 inHg= 0.006773 MPa
- 5 inHg= 0.016932 MPa
Inches of mercury to Bar
One inches of mercury is 0.033864 bar, and one bar is 29.52998 inches of mercury.
One bar is exactly 100,000 pascals, slightly less than one atmosphere. It is used for tyre pressure, industrial gases and weather charts.
- 1 inHg= 0.033864 bar
- 2 inHg= 0.067728 bar
- 5 inHg= 0.169319 bar
Inches of mercury to Millibar
One inches of mercury is 33.86389 millibar, and one millibar is 0.02953 inches of mercury.
A millibar is 100 pascals, identical to the hectopascal used in weather reports. Average sea-level pressure is about 1,013 millibars.
- 1 inHg= 33.86389 mbar
- 2 inHg= 67.72778 mbar
- 5 inHg= 169.31945 mbar
Inches of mercury to Atmospheres
One inches of mercury is 0.033421 atmospheres, and one atmospheres is 29.921252 inches of mercury.
One atmosphere is exactly 101,325 pascals, the average air pressure at sea level. It is used for gas calculations and diving tables.
- 1 inHg= 0.033421 atm
- 2 inHg= 0.066842 atm
- 5 inHg= 0.167105 atm
Inches of mercury to Pounds per square inch
One inches of mercury is 0.491154 pounds per square inch, and one pounds per square inch is 2.03602 inches of mercury.
One psi (pound per square inch) is 6,894.757293168 pascals. It is the tyre-pressure and hydraulic unit in the United States and the UK.
- 1 inHg= 0.491154 psi
- 2 inHg= 0.982308 psi
- 5 inHg= 2.455771 psi
Open the Inches of mercury to Pounds per square inch converter
Inches of mercury to Millimeters of mercury
One inches of mercury is 25.400003 millimeters of mercury, and one millimeters of mercury is 0.03937 inches of mercury.
One millimeter of mercury is 133.322387415 pascals. It is still used for blood-pressure readings, where 120/80 mmHg is the familiar healthy range.
- 1 inHg= 25.400003 mmHg
- 2 inHg= 50.800005 mmHg
- 5 inHg= 127.000013 mmHg
Open the Inches of mercury to Millimeters of mercury converter
What inches of mercury are used for
One inch of mercury is 3,386.389 pascals. It is used for barometric pressure and altimeter settings in aviation in the United States.
Bar, atmosphere and psi are exact definitions. Gauges and weather stations round heavily, so treat the last digit as indicative rather than precise.
Pressure units are all defined against the pascal, so the conversion is a multiplication by a fixed number. What makes this dimension awkward is that the numbers sit within tens of per cent of each other, so a small slip looks plausible.
Three of the units are close together on purpose: one bar is 100,000 pascals, one atmosphere is 101,325, and weather reports use millibars and hectopascals, which are the same size. A reading that looks like a unit error is often a genuine difference between gauge pressure and absolute pressure instead.
Checking a pressure conversion means converting through pascals and comparing with a known reference, such as the fact that a bar and an atmosphere differ by about 1.3%. The error to watch for is quoting a pressure without saying whether it is measured above atmospheric pressure or from a vacuum.
Inches of mercury conversion tables
Inches of mercury to Pascals
| Inches of mercury (inHg) | Pascals (Pa) |
|---|---|
| 1 | 3,386.389 |
| 2 | 6,772.778 |
| 3 | 10,159.167 |
| 4 | 13,545.556 |
| 5 | 16,931.945 |
| 10 | 33,863.89 |
| 25 | 84,659.725 |
| 50 | 169,319.45 |
| 100 | 338,638.9 |
Inches of mercury to Kilopascals
| Inches of mercury (inHg) | Kilopascals (kPa) |
|---|---|
| 1 | 3.386389 |
| 2 | 6.772778 |
| 3 | 10.159167 |
| 4 | 13.545556 |
| 5 | 16.931945 |
| 10 | 33.86389 |
| 25 | 84.659725 |
| 50 | 169.31945 |
| 100 | 338.6389 |
Inches of mercury to Megapascals
| Inches of mercury (inHg) | Megapascals (MPa) |
|---|---|
| 1 | 0.003386 |
| 2 | 0.006773 |
| 3 | 0.010159 |
| 4 | 0.013546 |
| 5 | 0.016932 |
| 10 | 0.033864 |
| 25 | 0.08466 |
| 50 | 0.169319 |
| 100 | 0.338639 |