Convert Millimeters of Mercury to Bars
Convert Millimeters of Mercury (mmHg) to Bars (bar) instantly and accurately.
Conversion Formula
bar = mmHg × 0.001333223874
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.
About Bars
A bar = exactly 100,000 Pa ≈ 0.987 atm - the world standard for industrial pressure outside North America. Hydraulic systems, pneumatic equipment, gas cylinders, dive computers, and tyre gauges in Europe and Asia use bar. Scuba diving: +1 bar per 10 m depth; at 40 m recreational limit = 5 bar absolute. European tyre pressure labels show bar alongside kPa. Industrial processes: steam at 10-50 bar; high-pressure reactors 100-300 bar; water-jet cutting 1,000-4,000 bar. 1 bar = 100,000 Pa = 14.504 psi.
Quick Reference Table
| Millimeters of Mercury (mmHg) | Bars (bar) |
|---|---|
| 1 mmHg | 0.00133322 bar |
| 2 mmHg | 0.00266645 bar |
| 5 mmHg | 0.00666612 bar |
| 10 mmHg | 0.0133322 bar |
| 25 mmHg | 0.0333306 bar |
| 50 mmHg | 0.0666612 bar |
| 100 mmHg | 0.133322 bar |