Convert Hectopascals to Millimeters of Mercury
Convert Hectopascals (hPa) to Millimeters of Mercury (mmHg) instantly and accurately.
Conversion Formula
mmHg = hPa × 0.7500615758
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.
About Millimeters of Mercury
One millimetre of mercury (mmHg) = pressure from 1 mm of mercury at 0°C and standard gravity = 133.322 Pa. Clinical medicine worldwide uses mmHg for blood pressure (normal ~120/80 mmHg) and for gas partial pressures in physiology: arterial O₂ ~95-100 mmHg; CO₂ ~40 mmHg; alveolar O₂ ~104 mmHg. Ophthalmologists measure intraocular pressure in mmHg (normal 10-21; glaucoma risk above 21). Vacuum equipment ratings are also given in mmHg. 760 mmHg = 1 atm. 1 mmHg = 133.322 Pa.
Quick Reference Table
| Hectopascals (hPa) | Millimeters of Mercury (mmHg) |
|---|---|
| 1 hPa | 0.750062 mmHg |
| 2 hPa | 1.50012 mmHg |
| 5 hPa | 3.75031 mmHg |
| 10 hPa | 7.50062 mmHg |
| 25 hPa | 18.7515 mmHg |
| 50 hPa | 37.5031 mmHg |
| 100 hPa | 75.0062 mmHg |