Convert Inches of Mercury to Bar
Instantly convert Inches of Mercury (inHg) to Bar (bar) with our free online calculator.
Formula: inHg to bar — multiply by 0.0338639
Reference Table
| Inches of Mercury (inHg) | Bar (bar) |
|---|---|
| 1 | 0.0338639 |
| 5 | 0.16932 |
| 10 | 0.338639 |
| 25 | 0.846598 |
| 50 | 1.6932 |
| 100 | 3.38639 |
How to Convert Inches of Mercury to Bar
Formula
To convert Inches of Mercury (inHg) to Bar (bar): multiply by 0.0338639
Step-by-Step
- Start with your value in Inches of Mercury (inHg).
- Multiply by 0.0338639 to perform the conversion.
- The result is your value expressed in Bar (bar).
Conversion Factor
1 inHg = 0.0338639 bar
Reverse Factor
1 bar = 29.53 inHg
Worked Example
Convert 25 Inches of Mercury to Bar: 25 inHg = 0.846598 bar
About Inch of Mercury (inHg)
A pressure unit defined as the pressure exerted by a 1-inch column of mercury at the standard density of mercury (0 °C) and the standard acceleration of gravity (≈ 3,386.389 Pa per NIST SP 811). Inches of mercury are the primary unit in US aviation for altimeter settings (the QNH datum is reported in inHg in METAR weather observations — "Altimeter 30.12 inHg" means 30.12 inHg corrected to mean sea level), US barometric weather reporting on consumer indoor weather stations and TV weather graphics, HVAC and refrigeration duct/return static pressure (often quoted as fractions of an inHg, e.g., 0.25 inHg = ~62 Pa), and some legacy automotive vacuum gauges measuring intake-manifold vacuum below atmospheric (a healthy engine reads ~18-22 inHg of vacuum at idle). Standard sea-level atmospheric pressure is 29.92 inHg = 1013.25 hPa = 101.325 kPa.
About Bar (bar)
A metric unit of pressure equal to exactly 100,000 pascals (100 kPa), approximately the average sea-level atmospheric pressure on Earth (1 atm = 1.01325 bar). Defined by IUPAC and accepted for use with the SI by the BIPM, the bar is not itself an SI-proper unit but is universally recognized in engineering. Bars are the default unit in European industry for compressed gas systems (compressed air at 6-10 bar shop pressure), hydraulics (mobile equipment at 200-400 bar working pressure), and chemical process plants. Car tire pressures in much of the world outside the US are specified in bar (a typical passenger car runs ~2.2 bar / 32 psi cold). Gauges on scuba cylinders (200 bar fill / ~2900 psi), brewery CO₂ tanks, fire suppression systems, and espresso machines (9 bar extraction pressure) all read in bar. 1 bar = 14.504 psi = 100 kPa = 0.9869 atm.
Quick Facts
- 1 Inch of Mercury equals 0.0338639 Bar
- 1 Bar equals 29.53 Inches of Mercury
- Inch of Mercury is a unit of pressure
- Bar is a unit of pressure
- This conversion is commonly used in tire inflation, weather reporting, scuba diving, and engineering
- The Inch of Mercury belongs to the imperial system
- The Bar belongs to the metric system
Common Inch of Mercury to Bar Conversions
| Inches of Mercury (inHg) | Bar (bar) |
|---|---|
| 0.1 | 0.00338639 |
| 0.5 | 0.0169319 |
| 1 | 0.0338639 |
| 2 | 0.0677278 |
| 5 | 0.16932 |
| 10 | 0.338639 |
| 14.696 | 0.497664 |
| 15 | 0.507958 |
| 20 | 0.677278 |
| 25 | 0.846598 |
| 50 | 1.6932 |
| 100 | 3.38639 |
| 150 | 5.07958 |
| 200 | 6.77278 |
| 500 | 16.932 |
| 1000 | 33.8639 |
Understanding Inches of Mercury
The Inch of Mercury (symbol: inHg) is a unit of pressure. A pressure unit defined as the pressure exerted by a 1-inch column of mercury at the standard density of mercury (0 °C) and the standard acceleration of gravity (≈ 3,386.389 Pa per NIST SP 811). Inches of mercury are the primary unit in US aviation for altimeter settings (the QNH datum is reported in inHg in METAR weather observations — "Altimeter 30.12 inHg" means 30.12 inHg corrected to mean sea level), US barometric weather reporting on consumer indoor weather stations and TV weather graphics, HVAC and refrigeration duct/return static pressure (often quoted as fractions of an inHg, e.g., 0.25 inHg = ~62 Pa), and some legacy automotive vacuum gauges measuring intake-manifold vacuum below atmospheric (a healthy engine reads ~18-22 inHg of vacuum at idle). Standard sea-level atmospheric pressure is 29.92 inHg = 1013.25 hPa = 101.325 kPa.
It belongs to the imperial measurement system.
Inches of Mercury are commonly used in tire inflation, weather reporting, scuba diving, and engineering.
Understanding Bar
The Bar (symbol: bar) is a unit of pressure. A metric unit of pressure equal to exactly 100,000 pascals (100 kPa), approximately the average sea-level atmospheric pressure on Earth (1 atm = 1.01325 bar). Defined by IUPAC and accepted for use with the SI by the BIPM, the bar is not itself an SI-proper unit but is universally recognized in engineering. Bars are the default unit in European industry for compressed gas systems (compressed air at 6-10 bar shop pressure), hydraulics (mobile equipment at 200-400 bar working pressure), and chemical process plants. Car tire pressures in much of the world outside the US are specified in bar (a typical passenger car runs ~2.2 bar / 32 psi cold). Gauges on scuba cylinders (200 bar fill / ~2900 psi), brewery CO₂ tanks, fire suppression systems, and espresso machines (9 bar extraction pressure) all read in bar. 1 bar = 14.504 psi = 100 kPa = 0.9869 atm.
It belongs to the metric measurement system.
Bar are commonly used in tire inflation, weather reporting, scuba diving, and engineering.
Why Convert Inches of Mercury to Bar?
Engineers, mechanics, and scientists frequently need to convert pressure between Inches of Mercury and Bar when working with different measurement standards. Tire pressure, blood pressure readings, weather barometric measurements, and industrial process specifications may all use different pressure units depending on the region or discipline. Reliable conversion prevents equipment misuse and ensures safety.
Frequently Asked Questions
How do I convert Inches of Mercury to Bar?
A pressure unit defined as the pressure exerted by a 1-inch column of mercury at the standard density of mercury (0 °C) and the standard acceleration of gravity (≈ 3,386. To convert Inches of Mercury to Bar, multiply by 0.0338639. For example, 25 inHg equals 0.846598 bar.
How many Bar are in 1 Inch of Mercury?
There are 0.0338639 Bar in 1 Inch of Mercury.
How many Inches of Mercury are in 1 Bar?
There are 29.53 Inches of Mercury in 1 Bar.
What is the formula for Inch of Mercury to Bar conversion?
The formula is: multiply by 0.0338639. This means 1 inHg = 0.0338639 bar.
Is a Inch of Mercury bigger than a Bar?
Yes. One Inch of Mercury is larger than one Bar because 1 inHg equals 0.0338639 bar, which is less than 1.
When do you need to convert between Inches of Mercury and Bar?
A metric unit of pressure equal to exactly 100,000 pascals (100 kPa), approximately the average sea-level atmospheric pressure on Earth (1 atm = 1. Inch of Mercury and Bar are both pressure units, so conversion comes up whenever one source of information uses one unit and another uses the other — a classic cross-reference challenge in engineering, trade, travel, and everyday life.