Convert Inch of mercury to Pascal
1 inch of mercury = 3,386.389 pascal (Pa). For example, 10 inch of mercury = 33,863.89 pascal and 100 inch of mercury = 338,638.9 pascal. Type any value below to convert inch of mercury to pascal both ways — it runs entirely in your browser.
Quick answer: Inch of mercury to Pascal
1 Inch of mercury = 3,386.389 Pascal (inHg → Pa). To convert inch of mercury to pascal, multiply by 3,386.389. To convert pascal to inch of mercury, multiply by 0.0002952998. The converter at the top does this instantly and both ways; the sections below give the formula, worked examples, a full conversion chart and answers to the most common inch of mercury-to-pascal questions.
How to convert Inch of mercury to Pascal
To convert inch of mercury to pascal, multiply the number of inch of mercury by the conversion factor 3,386.389, because 1 inHg = 3,386.389 Pa. The conversion is linear, so the same factor works for any value — whole numbers, decimals or fractions. For the reverse direction, 1 Pa = 0.0002952998 inHg, so you divide by 3,386.389 (or multiply by 0.0002952998) to turn pascal back into inch of mercury.
Pa = inHg × 3,386.389 ·
inHg = Pa × 0.0002952998
- Write down the value you want to convert, in inch of mercury.
- Multiply it by 3,386.389.
- The result is the same area/length/quantity expressed in pascal.
Inch of mercury to Pascal — worked examples
Each row shows the exact arithmetic so you can follow the conversion step by step. For example, 5 inch of mercury is 16,931.94 pascal because 5 inHg × 3,386.389 = 16,931.94 Pa.
| Inch of mercury | Calculation | Pascal |
|---|---|---|
| 1 inHg | 1 inHg × 3,386.389 = 3,386.389 Pa | 3,386.389 Pa |
| 2 inHg | 2 inHg × 3,386.389 = 6,772.777 Pa | 6,772.777 Pa |
| 3 inHg | 3 inHg × 3,386.389 = 10,159.17 Pa | 10,159.17 Pa |
| 5 inHg | 5 inHg × 3,386.389 = 16,931.94 Pa | 16,931.94 Pa |
| 7 inHg | 7 inHg × 3,386.389 = 23,704.72 Pa | 23,704.72 Pa |
| 10 inHg | 10 inHg × 3,386.389 = 33,863.89 Pa | 33,863.89 Pa |
| 12 inHg | 12 inHg × 3,386.389 = 40,636.66 Pa | 40,636.66 Pa |
| 15 inHg | 15 inHg × 3,386.389 = 50,795.83 Pa | 50,795.83 Pa |
| 20 inHg | 20 inHg × 3,386.389 = 67,727.77 Pa | 67,727.77 Pa |
| 25 inHg | 25 inHg × 3,386.389 = 84,659.72 Pa | 84,659.72 Pa |
| 50 inHg | 50 inHg × 3,386.389 = 169,319.4 Pa | 169,319.4 Pa |
| 100 inHg | 100 inHg × 3,386.389 = 338,638.9 Pa | 338,638.9 Pa |
Common Inch of mercury to Pascal conversions
These are the inch of mercury-to-pascal values people look up most often. Every figure is computed from the exact factor, so you can rely on them for quick reference:
- 1 inch of mercury = 3,386.389 pascal
- 2 inch of mercury = 6,772.777 pascal
- 2.5 inch of mercury = 8,465.972 pascal
- 3 inch of mercury = 10,159.17 pascal
- 4 inch of mercury = 13,545.55 pascal
- 5 inch of mercury = 16,931.94 pascal
- 6 inch of mercury = 20,318.33 pascal
- 7 inch of mercury = 23,704.72 pascal
- 8 inch of mercury = 27,091.11 pascal
- 9 inch of mercury = 30,477.5 pascal
- 10 inch of mercury = 33,863.89 pascal
- 12 inch of mercury = 40,636.66 pascal
- 15 inch of mercury = 50,795.83 pascal
- 20 inch of mercury = 67,727.77 pascal
- 25 inch of mercury = 84,659.72 pascal
- 30 inch of mercury = 101,591.7 pascal
- 50 inch of mercury = 169,319.4 pascal
- 75 inch of mercury = 253,979.1 pascal
- 100 inch of mercury = 338,638.9 pascal
- 200 inch of mercury = 677,277.7 pascal
- 500 inch of mercury = 1,693,194 pascal
- 1000 inch of mercury = 3,386,389 pascal
Inch of mercury to Pascal conversion chart (both directions)
The chart below converts inch of mercury to pascal and pascal to inch of mercury side by side, so it works whichever way you need. 1 inch of mercury = 3,386.389 pascal, and 1 pascal = 0.0002952998 inch of mercury.
| Inch of mercury → Pascal | Pascal → Inch of mercury |
|---|---|
| 0.25 inHg = 846.5972 Pa | 0.25 Pa = 0.00007382496 inHg |
| 0.5 inHg = 1,693.194 Pa | 0.5 Pa = 0.0001476499 inHg |
| 1 inHg = 3,386.389 Pa | 1 Pa = 0.0002952998 inHg |
| 2 inHg = 6,772.777 Pa | 2 Pa = 0.0005905997 inHg |
| 3 inHg = 10,159.17 Pa | 3 Pa = 0.0008858995 inHg |
| 4 inHg = 13,545.55 Pa | 4 Pa = 0.001181199 inHg |
| 5 inHg = 16,931.94 Pa | 5 Pa = 0.001476499 inHg |
| 6 inHg = 20,318.33 Pa | 6 Pa = 0.001771799 inHg |
| 7 inHg = 23,704.72 Pa | 7 Pa = 0.002067099 inHg |
| 8 inHg = 27,091.11 Pa | 8 Pa = 0.002362399 inHg |
| 9 inHg = 30,477.5 Pa | 9 Pa = 0.002657698 inHg |
| 10 inHg = 33,863.89 Pa | 10 Pa = 0.002952998 inHg |
| 12 inHg = 40,636.66 Pa | 12 Pa = 0.003543598 inHg |
| 15 inHg = 50,795.83 Pa | 15 Pa = 0.004429497 inHg |
| 20 inHg = 67,727.77 Pa | 20 Pa = 0.005905997 inHg |
| 25 inHg = 84,659.72 Pa | 25 Pa = 0.007382496 inHg |
| 30 inHg = 101,591.7 Pa | 30 Pa = 0.008858995 inHg |
| 40 inHg = 135,455.5 Pa | 40 Pa = 0.01181199 inHg |
| 50 inHg = 169,319.4 Pa | 50 Pa = 0.01476499 inHg |
| 75 inHg = 253,979.1 Pa | 75 Pa = 0.02214749 inHg |
| 100 inHg = 338,638.9 Pa | 100 Pa = 0.02952998 inHg |
| 150 inHg = 507,958.3 Pa | 150 Pa = 0.04429497 inHg |
| 200 inHg = 677,277.7 Pa | 200 Pa = 0.05905997 inHg |
| 250 inHg = 846,597.2 Pa | 250 Pa = 0.07382496 inHg |
| 500 inHg = 1,693,194 Pa | 500 Pa = 0.1476499 inHg |
| 1000 inHg = 3,386,389 Pa | 1000 Pa = 0.2952998 inHg |
Inch of mercury vs Pascal: which is bigger?
A inch of mercury is the larger unit: one inch of mercury equals 3,386.389 pascals. Put another way, you need 3,386.389 pascals to make a single inch of mercury.
What is a Inch of mercury? History, origin and usage
Inches of mercury come from the same barometers as millimetres of mercury, read off in imperial units. The unit stayed embedded in North American practice long after the metric system spread elsewhere, largely because aviation and broadcast weather standardised on it early and changing would have meant reissuing every altimeter and every chart.
Inches of mercury are used for atmospheric pressure in United States weather reports and, importantly, for altimeter settings in aviation in the US and Canada. They also appear on vacuum gauges for engines and air-conditioning work.
The standard sea-level pressure of 29.92 inHg is one of the most recognisable numbers in aviation — pilots set it as the default altimeter reference. An inch of mercury is exactly 25.4 millimetres of mercury, because the inch itself has been exactly 25.4 mm since 1959.
What is a Pascal? History, origin and usage
The pascal is named after Blaise Pascal, who in 1648 had his brother-in-law carry a mercury barometer up the Puy de Dôme in central France and watch the mercury column fall as he climbed. That experiment showed air has weight and that the pressure it exerts drops with height. The unit itself is much younger: the name was adopted by the General Conference on Weights and Measures in 1971, replacing the older habit of writing pressures as "newtons per square metre".
The pascal is the SI unit of pressure and the base every other unit on this page is defined against. On its own it is awkwardly small for daily life — a sheet of paper resting on a table presses down with only a few pascals — so real-world figures are almost always given with a prefix: hectopascals for weather, kilopascals for tyres and gas, megapascals for concrete and hydraulics.
One pascal is one newton spread over one square metre, which is about the pressure of a five-rupee coin lying flat on a table. Because pressure is force divided by area, the same push concentrated into a smaller area gives a much higher pressure — which is why a drawing pin goes into a wall and your thumb does not.
Convert 1 Inch of mercury to other units
It can help to see a inch of mercury next to the other units it is commonly compared with. One inch of mercury (inHg) is equal to:
| 1 Inch of mercury equals | Unit |
|---|---|
| 3,386.389 Pa | Pascal |
| 33.86389 hPa | Hectopascal |
| 3.386389 kPa | Kilopascal |
| 0.003386389 MPa | Megapascal |
| 33.86389 mbar | Millibar |
| 0.03386389 bar | Bar |
| 0.03342106 atm | Standard atmosphere |
| 25.4 Torr | Torr |
| 25.4 mmHg | Millimetre of mercury |
| 345.3155 mmH₂O | Millimetre of water |
| 13.5951 inH₂O | Inch of water |
| 0.4911541 psi | Pound per square inch |
| 0.03453155 kgf/cm² | Kilogram-force per square centimetre |
Convert 1 Pascal to other units
One pascal (Pa) is equal to:
| 1 Pascal equals | Unit |
|---|---|
| 0.01 hPa | Hectopascal |
| 0.001 kPa | Kilopascal |
| 0.000001 MPa | Megapascal |
| 0.01 mbar | Millibar |
| 0.00001 bar | Bar |
| 0.000009869233 atm | Standard atmosphere |
| 0.007500617 Torr | Torr |
| 0.007500616 mmHg | Millimetre of mercury |
| 0.0002952998 inHg | Inch of mercury |
| 0.1019716 mmH₂O | Millimetre of water |
| 0.004014631 inH₂O | Inch of water |
| 0.0001450377 psi | Pound per square inch |
| 0.00001019716 kgf/cm² | Kilogram-force per square centimetre |
Tips for converting Inch of mercury to Pascal
- To go from inch of mercury to pascal, multiply by 3,386.389; to go back, divide by 3,386.389 (or multiply by 0.0002952998).
- For a quick mental estimate, remember that 1 inch of mercury ≈ 3,386.389 pascal, so 10 inch of mercury ≈ 33,863.89 pascal.
- The converter above keeps full precision; the tables round for readability, so use the tool for exact figures.
- Both fields update live as you type — change either side to convert in that direction.
How to use this Inch of mercury to Pascal converter
Type a number into the Inch of mercury field and the equivalent in Pascal appears instantly — there is no “convert” button to press and nothing is sent to a server, so it works offline once the page has loaded and is safe for any data. You can also type into the Pascal field to convert the other way (pascal to inch of mercury). Use the swap control to flip the two units, and copy the result with a single click. Because the calculation runs in your browser with full floating-point precision, the converter is more exact than the rounded figures shown in the reference chart above — use the chart for quick look-ups and the tool for precise work.
Accuracy and method
Every figure on this page — the formula, the worked examples, the conversion chart and the “convert to other units” tables — is computed from a single verified conversion factor (1 inHg = 3,386.389 Pa), never copied from a hand-typed lookup table that could drift. That factor is derived from each unit’s definition in terms of a common base unit, and an automated check re-verifies all of the site’s factors on every update, so the numbers here stay correct over time. This matters for inch of mercury-to-pascal conversions because a small rounding error in a published table compounds quickly at larger quantities; computing from the exact factor avoids that.
Sources
- NIST Special Publication 811 — Guide for the Use of the SI — publishes the exact metric equivalents of the customary pressure units. A psi is one pound of force over one square inch, and the 1959 international yard-and-pound agreement fixes the pound at exactly 0.453 592 37 kilogram and the inch at exactly 0.0254 metre, while standard gravity is fixed at exactly 9.806 65 m/s² — so psi, inches of mercury and inches of water are defined exactly rather than measured.
- BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.
Pressure factors here come from fixed definitions, anchored to the pascal: a bar is exactly 100,000 Pa, one atmosphere is exactly 101,325 Pa, a torr is exactly a 760th of an atmosphere, and psi is built from the exact pound and the exact inch. Two of them — psi and the torr — work out to decimals that repeat forever, so where a number is shown rounded it is marked, not quietly trimmed.
Frequently asked questions
- How many pascal are in 1 inch of mercury?
- 1 inch of mercury = 3,386.389 pascal (Pa). To convert any number of inch of mercury to pascal, multiply by 3,386.389.
- How do I convert inch of mercury to pascal?
- Multiply the number of inch of mercury by 3,386.389. For example, 10 inch of mercury = 10 × 3,386.389 = 33,863.89 pascal, and 25 inch of mercury = 84,659.72 pascal.
- How many inch of mercury are in 1 pascal?
- 1 pascal = 0.0002952998 inch of mercury. So to convert pascal back to inch of mercury, multiply by 0.0002952998.
- What is the formula to convert inch of mercury to pascal?
- pascal = inch of mercury × 3,386.389. The reverse formula is inch of mercury = pascal × 0.0002952998.
- How much is 100 inch of mercury in pascal?
- 100 inch of mercury = 338,638.9 pascal. (And 1000 inch of mercury = 3,386,389 pascal.)
- Which is bigger, a inch of mercury or a pascal?
- A inch of mercury is larger: 1 inch of mercury = 3,386.389 pascal.
- Is this inch of mercury to pascal converter accurate?
- Yes — every value is computed from the exact 3,386.389 Pa per inHg factor (not rounded look-up tables), and the factors are re-verified automatically on every update.
- Can I convert pascal to inch of mercury too?
- Yes. The converter works both ways — enter a value in either field. 1 pascal = 0.0002952998 inch of mercury.