3 Torr to mmHg — 3 torr in millimetres of mercury
Exact 3 ÷ 1 = 3
3 torr in other units
| Pascals | 399.967105 | Pa |
|---|---|---|
| Hectopascals | 3.999671 | hPa |
| Kilopascals | 0.39996711 | kPa |
| Megapascals | 0.000399967105 | MPa |
| Millibars | 3.999671 | mbar |
| Bar | 0.003999671053 | bar |
| Standard atmospheres | 0.003947368421 | atm |
| Pounds per square inch | 0.05801032 | psi |
| Millimetres of mercury | 3 | mmHg |
| Inches of mercury | 0.11811022 | inHg |
Torr to mmHg at a glance
| Torr | Millimetres of mercury |
|---|---|
| 1 Torr | 0.99999986 mmHg |
| 2 Torr | 2 mmHg |
| 3 Torr | 3 mmHg |
| 5 Torr | 4.999999 mmHg |
| 10 Torr | 9.999999 mmHg |
| 20 Torr | 19.999997 mmHg |
| 25 Torr | 24.999996 mmHg |
| 50 Torr | 49.999993 mmHg |
| 100 Torr | 99.999986 mmHg |
| 250 Torr | 249.999964 mmHg |
| 500 Torr | 499.999929 mmHg |
| 1,000 Torr | 999.999858 mmHg |
How to convert torr to millimetres of mercury
Multiply by 0.99999986 — one torr is 0.99999986 millimetres 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 3 ÷ 1 = 3
In words: about three millimetres of mercury.
What these units are
The torr and the millimetre of mercury are covered in the pressure unit guide, along with every other unit on this page.
Questions
How many millimetres of mercury are in a torr?
One torr is 0.99999986 millimetres of mercury. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 3 torr in millimetres of mercury?
3 torr is 3 millimetres of mercury. The working is 3 ÷ 1 = 3.
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.