This converter turns torr into millimeters of mercury instantly, using the exact factor 1 torr = 0.9999998575 millimeters of mercury. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
One millimetre of mercury, used in vacuum work. The clinical unit for blood pressure worldwide.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
torr- The amount you are converting, measured in torr
0.9999998575- The exact number of millimeters of mercury in one torr
millimeters of mercury- The converted result
How it works, step by step
- Enter the number of torr you want to convert.
- The value is multiplied by 0.9999998575, the exact conversion factor.
- The result is displayed in millimeters of mercury, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 torr
Multiply 5 by 0.99999986. That gives 5 millimeters of mercury. A quick sanity check: one torr is smaller than one millimeter of mercury, so the number should get smaller — and it does.
Converting 72 torr
72 × 0.99999986 = 72 millimeters of mercury. Working backwards, 72 ÷ 0.99999986 returns 72 torr, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many millimeters of mercury are in one torr?
Exactly 0.9999998575. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert torr to millimeters of mercury?
Millimeters Of Mercury = torr × 0.9999998575. To reverse it, divide instead: torr = millimeters of mercury ÷ 0.9999998575, which is the same as multiplying by 1.000000142.
Is the torr bigger than the millimeter of mercury?
No. One torr is only 1 of a millimeter of mercury, so the millimeter of mercury is the larger unit.
Why does my answer differ slightly from other torr to mmhg converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a torr?
One millimetre of mercury, used in vacuum work.
What is a millimeter of mercury?
The clinical unit for blood pressure worldwide.
Torr to millimeters of mercury reference table
| Torr | Millimeters Of Mercury |
|---|---|
| 0.5 Torr | 0.5 mmHg |
| 1 Torr | 1 mmHg |
| 2 Torr | 2 mmHg |
| 3 Torr | 3 mmHg |
| 5 Torr | 5 mmHg |
| 10 Torr | 10 mmHg |
| 15 Torr | 15 mmHg |
| 20 Torr | 20 mmHg |
| 25 Torr | 25 mmHg |
| 50 Torr | 50 mmHg |
| 75 Torr | 75 mmHg |
| 100 Torr | 100 mmHg |
| 250 Torr | 250 mmHg |
| 500 Torr | 499.9999 mmHg |
| 1000 Torr | 999.9999 mmHg |
Exact factor: 1 torr = 0.9999998575 millimeters of mercury. Values rounded for display.