How to Convert Inches of mercury to Bar (inHg to bar)
Pressure conversions are used for tyre pressure (psi or bar), blood pressure readings in mmHg and weather maps in millibars. This guide shows how to convert inches of mercury into bar by hand, with examples and a quick-reference table.
The conversion
To convert inches of mercury to bar, multiply the value by 0.03386389. To go the other way, divide by the same number (or multiply by 29.5299801647). For a quick estimate, multiply by about 0.034.
Bar = inches of mercury × 0.03386389
Worked examples
- 3 inHg = 0.101592 bar
- 12.5 inHg = 0.423299 bar
- 75 inHg = 2.5398 bar
Inches of mercury to Bar table
| Inches of mercury | Bar |
|---|---|
| 1 inHg | 0.033864 bar |
| 2 inHg | 0.067728 bar |
| 5 inHg | 0.169319 bar |
| 10 inHg | 0.338639 bar |
| 20 inHg | 0.677278 bar |
| 25 inHg | 0.846597 bar |
| 50 inHg | 1.6932 bar |
| 100 inHg | 3.3864 bar |
| 250 inHg | 8.466 bar |
| 500 inHg | 16.9319 bar |
| 1,000 inHg | 33.8639 bar |
Common questions
Is inHg to bar exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Bar to Inches of mercury converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Forgetting squared and cubed units
Area and volume factors are the length factor squared or cubed, so 1 m² is about 10.76 sq ft, not 3.28.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
For any value, use the Inches of mercury to Bar Converter or browse all pressure converters.
Run your own numbers: Inches of mercury to Bar Converter