• inHg   Pa
  •  
Rounding Mode:

The “inch of mercury” (inHg) is a unit of pressure commonly used in aviation, meteorology, and refrigeration. It originates from the barometric pressure measurement practice using a column of mercury. This unit became a staple due to its early adoption in weather forecasting and its accurate and consistent measurements. An interesting fact is that an inch of mercury is approximately equal to 33.86 millibars or 3386 Pascals, but what truly distinguishes it is its historical significance in the development of modern atmospheric science.

In the 17th century, Evangelista Torricelli, a student of Galileo, first discovered that atmospheric pressure could sustain a column of mercury, laying the groundwork for this unit. His invention, the barometer, revolutionized how we understand and predict weather, marking the inch of mercury as more than just a unit—it’s a nod to the evolution of scientific inquiry and practice.

Did you know?

The Pascal, named after the French mathematician and physicist Blaise Pascal, is the SI unit of pressure. It is equivalent to one newton per square meter, symbolized as Pa. Despite its relatively recent introduction in 1971, the Pascal honors the pioneering work of Pascal in fluid mechanics and pressure, such as Pascal’s Law, which explains how pressure applied to a confined fluid is transmitted undiminished in all directions. Interestingly, a single Pascal is a tiny unit of pressure, roughly equal to the pressure exerted by a dollar bill resting flat on a table. This illustrates why everyday atmospheric pressure is typically measured in kilopascals (kPa), as one standard atmosphere is about 101.3 kPa.

> Inches of mercury to Pascals Conversion Table

Inches of mercury Pascals
0 inHg 0 Pa
1 inHg 3386.38895 Pa
2 inHg 6772.77791 Pa
3 inHg 10159.16686 Pa
4 inHg 13545.55581 Pa
5 inHg 16931.94477 Pa
6 inHg 20318.33372 Pa
7 inHg 23704.72267 Pa
8 inHg 27091.11163 Pa
9 inHg 30477.50058 Pa
10 inHg 33863.88953 Pa
11 inHg 37250.27849 Pa
12 inHg 40636.66744 Pa
13 inHg 44023.05639 Pa
14 inHg 47409.44535 Pa
15 inHg 50795.8343 Pa
16 inHg 54182.22325 Pa
17 inHg 57568.61221 Pa
18 inHg 60955.00116 Pa
19 inHg 64341.39011 Pa
20 inHg 67727.77907 Pa
21 inHg 71114.16802 Pa
22 inHg 74500.55697 Pa
23 inHg 77886.94593 Pa
24 inHg 81273.33488 Pa
25 inHg 84659.72383 Pa
26 inHg 88046.11278 Pa
27 inHg 91432.50174 Pa
28 inHg 94818.89069 Pa
29 inHg 98205.27964 Pa
30 inHg 101591.6686 Pa
31 inHg 104978.05755 Pa
32 inHg 108364.4465 Pa
33 inHg 111750.83546 Pa
34 inHg 115137.22441 Pa
35 inHg 118523.61336 Pa
36 inHg 121910.00232 Pa
37 inHg 125296.39127 Pa
38 inHg 128682.78022 Pa
39 inHg 132069.16918 Pa
40 inHg 135455.55813 Pa
41 inHg 138841.94708 Pa
42 inHg 142228.33604 Pa
43 inHg 145614.72499 Pa
44 inHg 149001.11394 Pa
45 inHg 152387.5029 Pa
46 inHg 155773.89185 Pa
47 inHg 159160.2808 Pa
48 inHg 162546.66976 Pa
49 inHg 165933.05871 Pa
50 inHg 169319.44766 Pa
51 inHg 172705.83662 Pa
52 inHg 176092.22557 Pa
53 inHg 179478.61452 Pa
54 inHg 182865.00348 Pa
55 inHg 186251.39243 Pa
56 inHg 189637.78138 Pa
57 inHg 193024.17034 Pa
58 inHg 196410.55929 Pa
59 inHg 199796.94824 Pa
60 inHg 203183.3372 Pa
61 inHg 206569.72615 Pa
62 inHg 209956.1151 Pa
63 inHg 213342.50406 Pa
64 inHg 216728.89301 Pa
65 inHg 220115.28196 Pa
66 inHg 223501.67092 Pa
67 inHg 226888.05987 Pa
68 inHg 230274.44882 Pa
69 inHg 233660.83778 Pa
70 inHg 237047.22673 Pa
71 inHg 240433.61568 Pa
72 inHg 243820.00463 Pa
73 inHg 247206.39359 Pa
74 inHg 250592.78254 Pa
75 inHg 253979.17149 Pa
76 inHg 257365.56045 Pa
77 inHg 260751.9494 Pa
78 inHg 264138.33835 Pa
79 inHg 267524.72731 Pa
80 inHg 270911.11626 Pa
81 inHg 274297.50521 Pa
82 inHg 277683.89417 Pa
83 inHg 281070.28312 Pa
84 inHg 284456.67207 Pa
85 inHg 287843.06103 Pa
86 inHg 291229.44998 Pa
87 inHg 294615.83893 Pa
88 inHg 298002.22789 Pa
89 inHg 301388.61684 Pa
90 inHg 304775.00579 Pa
91 inHg 308161.39475 Pa
92 inHg 311547.7837 Pa
93 inHg 314934.17265 Pa
94 inHg 318320.56161 Pa
95 inHg 321706.95056 Pa
96 inHg 325093.33951 Pa
97 inHg 328479.72847 Pa
98 inHg 331866.11742 Pa
99 inHg 335252.50637 Pa
100 inHg 338638.89533 Pa