mmHg to inHg Converter

How to convert millimeters of mercury to inches of mercury

FormulainHg = mmHg × 0.03937007874

Because one inch of mercury equals 25.4 millimeters of mercury, you can also divide: inHg = mmHg ÷ 25.4.

A millimeter of mercury is smaller than an inch of mercury: it takes 25.4 millimeters of mercury to make one inch of mercury.

Worked examples

1 millimeter of mercury1 mmHg × 0.03937007874 = 0.03937007874 inHg
5 millimeters of mercury5 mmHg × 0.03937007874 = 0.1968503937 inHg
10 millimeters of mercury10 mmHg × 0.03937007874 = 0.3937007874 inHg
20 millimeters of mercury20 mmHg × 0.03937007874 = 0.7874015748 inHg
100 millimeters of mercury100 mmHg × 0.03937007874 = 3.937007874 inHg

Millimeters of mercury to inches of mercury conversion table

Values are calculated by the conversion engine and rounded to 8 significant figures.

Millimeters of mercury to inches of mercury: 0.1–10 mmHg
Millimeters of mercury (mmHg)	Inches of mercury (inHg)
0.1 mmHg	0.0039370079 inHg
0.25 mmHg	0.0098425197 inHg
0.5 mmHg	0.019685039 inHg
1 mmHg	0.039370079 inHg
2 mmHg	0.078740157 inHg
3 mmHg	0.11811024 inHg
4 mmHg	0.15748031 inHg
5 mmHg	0.19685039 inHg
6 mmHg	0.23622047 inHg
7 mmHg	0.27559055 inHg
8 mmHg	0.31496063 inHg
9 mmHg	0.35433071 inHg
10 mmHg	0.39370079 inHg

Millimeters of mercury to inches of mercury: 12–1,000 mmHg
Millimeters of mercury (mmHg)	Inches of mercury (inHg)
12 mmHg	0.47244094 inHg
15 mmHg	0.59055118 inHg
20 mmHg	0.78740157 inHg
25 mmHg	0.98425197 inHg
30 mmHg	1.1811024 inHg
40 mmHg	1.5748031 inHg
50 mmHg	1.9685039 inHg
75 mmHg	2.9527559 inHg
100 mmHg	3.9370079 inHg
250 mmHg	9.8425197 inHg
500 mmHg	19.685039 inHg
1,000 mmHg	39.370079 inHg

About the units

Millimeter of mercury (mmHg)

The conventional mmHg is 133.322387415 Pa. Blood pressure is measured in mmHg (e.g. 120/80).

Inch of mercury (inHg)

About 3,386.39 Pa. US weather reports and aircraft altimeters use inches of mercury (standard is 29.92 inHg). One inch of mercury equals 3,386.38864 pascals (Pa).

Frequently asked questions

How many inches of mercury are in one millimeter of mercury?

There are 0.03937007874 inches of mercury in one millimeter of mercury, and this value is exact by definition.

How do I convert millimeters of mercury to inches of mercury?

Multiply the number of millimeters of mercury by 0.03937007874. For example, 10 mmHg × 0.03937007874 = 0.3937007874 inHg.

How many millimeters of mercury are in one inch of mercury?

One inch of mercury equals 25.4 millimeters of mercury. That is the reverse factor, 1 ÷ 0.03937007874.

What is 10 millimeters of mercury in inches of mercury?

10 mmHg = 0.3937007874 inHg.

Is this mmHg to inHg converter accurate?

Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.