📊 inHg to kPa Converter
Instantly convert pressure from inches of mercury (inHg) to kilopascals (kPa). 1 inHg is exactly 3.38639 kPa. Essential for barometric pressure readings, vacuum systems, and aviation applications.
What Is Inches of Mercury (inHg)?
Inches of mercury (inHg) is a unit of pressure measurement based on the height of a column of mercury that the pressure can support. It is commonly used in:
- Barometric pressure — weather forecasts and altimeter settings in aviation.
- Aviation — aircraft altimeters are calibrated in inches of mercury.
- Vacuum systems — measuring vacuum levels in industrial processes.
- HVAC — refrigerant pressure measurements.
Standard atmospheric pressure at sea level is 29.92 inHg (101.325 kPa).
What Is Kilopascal (kPa)?
The kilopascal (kPa) is a unit of pressure in the International System of Units (SI), equal to 1,000 pascals. It is commonly used in:
- Meteorology — atmospheric pressure in most countries.
- Engineering — structural, mechanical, and civil engineering.
- Automotive — tire pressure in many countries.
- Industrial — hydraulic and pneumatic systems.
How to Convert inHg to kPa
The formula to convert inHg to kPa is:
kPa = inHg × 3.38639
or kPa = inHg × 3.38639
For example, to convert 29.92 inHg (standard atmospheric pressure) to kPa:
kPa = 29.92 × 3.38639
kPa = 101.325 kPa
To convert a common vacuum reading of 20 inHg to kPa:
kPa = 20 × 3.38639
kPa = 67.728 kPa
Why Use This Converter?
- Instant results: Get accurate inHg to kPa conversions in real-time.
- Step-by-step breakdown: See exactly how the conversion is calculated.
- Common reference table: Quickly check pressure values from 5 inHg to 100 inHg.
- Free & private: No registration, no data storage — all calculations are done in your browser.
❓ inHg to kPa FAQ
What is the formula to convert inHg to kPa?
The formula is kPa = inHg × 3.38639.
How many kPa is 1 inHg?
1 inHg is equal to 3.38639 kPa.
How many inHg is 1 kPa?
1 kPa is equal to 0.29530 inHg.
What is standard atmospheric pressure in inHg and kPa?
Standard atmospheric pressure at sea level is 29.92 inHg or 101.325 kPa.
What is the difference between inHg and kPa?
inHg (inches of mercury) is a traditional unit based on a mercury barometer, commonly used in the United States for weather and aviation. kPa (kilopascals) is the SI-derived unit used in most other countries for pressure measurements.
Where is inHg commonly used?
inHg is commonly used in the United States for barometric pressure readings, aviation altimeter settings, and some industrial applications.
Where is kPa commonly used?
kPa is used in most countries worldwide for meteorology, engineering, automotive tire pressure, and industrial applications.
How accurate is this converter?
This converter uses the exact conversion factor 3.38639 for high accuracy. You can adjust the decimal precision to suit your needs.
Is this converter free?
Yes, this converter is completely free to use. No registration or personal data storage is required.
What is a typical vacuum reading in inHg?
Common vacuum readings range from 10–29.92 inHg, corresponding to 33.86–101.33 kPa. A perfect vacuum would be 0 inHg (0 kPa), but this is unattainable in practice.