100 psi to inHg — 100 pounds per square inch in inches of mercury
Exact 100 × 2.036021 = 203.602068
100 pounds per square inch in other units
| Pascals | 689,475.73 | Pa |
|---|---|---|
| Hectopascals | 6,894.76 | hPa |
| Kilopascals | 689.475729 | kPa |
| Megapascals | 0.68947573 | MPa |
| Millibars | 6,894.76 | mbar |
| Bar | 6.894757 | bar |
| Standard atmospheres | 6.804596 | atm |
| Torr | 5,171.49 | Torr |
| Millimetres of mercury | 5,171.49 | mmHg |
| Inches of mercury | 203.602068 | inHg |
psi to inHg at a glance
| Pounds per square inch | Inches of mercury |
|---|---|
| 1 psi | 2.036021 inHg |
| 2 psi | 4.072041 inHg |
| 3 psi | 6.108062 inHg |
| 5 psi | 10.180103 inHg |
| 10 psi | 20.360207 inHg |
| 20 psi | 40.720414 inHg |
| 25 psi | 50.900517 inHg |
| 50 psi | 101.801034 inHg |
| 100 psi | 203.602068 inHg |
| 250 psi | 509.005169 inHg |
| 500 psi | 1,018.01 inHg |
| 1,000 psi | 2,036.02 inHg |
How to convert pounds per square inch to inches of mercury
Multiply by 2.036021 — one pound per square inch is 2.036021 inches of mercury. That factor is exact: it comes from the definition of the units rather than from a measurement, so it will not change and does not need rounding.
Working 100 × 2.036021 = 203.602068
In words: about two hundred four inches of mercury.
What these units are
The pound per square inch and the inch of mercury are covered in the pressure unit guide, along with every other unit on this page.
Questions
How many inches of mercury are in a pound per square inch?
One pound per square inch is 2.036021 inches of mercury. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 100 pounds per square inch in inches of mercury?
100 pounds per square inch is 203.602068 inches of mercury. The working is 100 × 2.036021 = 203.602068.
What pressure should my tyres be?
Look at the sticker in the driver's door frame or the fuel flap, not the number moulded into the tyre — that one is the tyre's maximum, not the manufacturer's recommendation. Most cars sit somewhere around 32 to 35 psi, which is roughly 2.2 to 2.4 bar.
Is my tyre gauge measuring absolute or gauge pressure?
Gauge pressure — the amount above the surrounding air. A tyre reading 32 psi actually contains about 46.7 psi absolute, because atmospheric pressure of roughly 14.7 psi is already pressing on the other side of the gauge. Conversions on this page are between units, and leave that distinction alone.
Why do weather forecasts use hectopascals and millibars interchangeably?
Because they are the same size. One hectopascal is exactly one millibar, so the change from mbar to hPa was a relabelling rather than a conversion. Standard sea-level pressure is 1013.25 of either.
What is the difference between torr and mmHg?
Almost nothing, and the difference is deliberate. A torr is exactly one seven-hundred-and-sixtieth of a standard atmosphere; the conventional mmHg is defined as exactly 133.322387415 pascals. They diverge by about one part in seven million — invisible in medicine, occasionally not in vacuum work.