Inches of Mercury to Millibars Converter
1 inch of mercury = 33.8639 millibars.
Enter a value
Result
1 inch of mercury =
33.8639 mbar
1 inHg × 33.8639 = 33.8639 mbar
1 atm = 101,325 Pa · 1 bar = 100,000 Pa
The working
- 1. Convert 1 inHg to pascals: 1 × 3,386.39 = 3,386.39.
- 2. Convert to mbar: 3,386.39 ÷ 100 = 33.8639.
1 inHg in every unit
Common pressures
- Car tyre
- 2.2 bar (32 psi)
- Road bike tyre
- 6-8 bar
- Sea-level air pressure
- 1,013 mbar
- Normal blood pressure
- 120/80 mmHg
Conversion table
Inches of mercury to Millibars
| Inches of mercury | Millibars |
|---|---|
| 28 | 948.19 |
| 28.5 | 965.12 |
| 29 | 982.05 |
| 29.5 | 998.98 |
| 29.92 | 1,013.2 |
| 30 | 1,015.9 |
| 30.5 | 1,032.8 |
| 31 | 1,049.8 |
Millibars to Inches of mercury
| Millibars | Inches of mercury |
|---|---|
| 28 | 0.82684 |
| 28.5 | 0.8416 |
| 29 | 0.85637 |
| 29.5 | 0.87113 |
| 29.92 | 0.88354 |
| 30 | 0.8859 |
| 30.5 | 0.90066 |
| 31 | 0.91543 |
Formula and worked example
millibars = inches of mercury × 33.86389.
Convert 29.92 inches of mercury to millibars: 29.92 × 33.86389 = 1,013.21 mbar.
When you need this
US weather reports and aircraft altimeters give pressure in inches of mercury, while most other forecasts use millibars (hectopascals).
Questions people ask
How many millibars are in a inch of mercury?
One inch of mercury is 33.86389 millibars.
How do I convert inches of mercury to millibars?
Multiply the number of inches of mercury by 33.86389.
What is 29.92 inHg in mbar?
29.92 inches of mercury is 1,013.21 millibars.
How do I convert millibars back to inches of mercury?
Multiply by 0.02952998: one millibar is 0.02952998 inches of mercury.
Related conversions
How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it. Source: NIST Special Publication 811, Guide for the Use of the International System of Units.
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