Convert Inches of Mercury to Hectopascals
Convert Inches of Mercury (inHg) to Hectopascals (hPa) instantly and accurately.
Conversion Formula
hPa = inHg × 33.8638864
About Inches of Mercury
One inch of mercury (inHg) ≈ 3,386 Pa - the primary barometric pressure unit in US aviation and meteorology. ASOS weather stations, METARs, and altimeter settings in the US report in inHg. Standard sea-level pressure is 29.92 inHg. Altimeters are set to local QNH in inHg to maintain altitude reference. US barometers for home weather stations display inHg. Typical pressure range: 28.5-31.0 inHg in continental weather systems. Record low: ~25.70 inHg (Typhoon Tip, 1979). 1 inHg = 3,386.39 Pa.
About Hectopascals
A hectopascal (hPa) = 100 Pa = 1 mbar - the WMO-official SI-compatible meteorological pressure unit since 1986, replacing millibar with no numerical change. All modern surface observations (METAR, SYNOP), digital barometers, aviation weather, and weather apps report in hPa. QNH altimeter settings outside North America are in hPa. ICAO standard sea-level pressure is 1013.25 hPa. Continental high-pressure record exceeds 1084 hPa; Typhoon Tip (1979) holds the low record at ~870 hPa. 1 hPa = 100 Pa.
Quick Reference Table
| Inches of Mercury (inHg) | Hectopascals (hPa) |
|---|---|
| 1 inHg | 33.8639 hPa |
| 2 inHg | 67.7278 hPa |
| 5 inHg | 169.319 hPa |
| 10 inHg | 338.639 hPa |
| 25 inHg | 846.597 hPa |
| 50 inHg | 1693.19 hPa |
| 100 inHg | 3386.39 hPa |