Turn on any American weather broadcast and the meteorologist will say the barometer reads 29.92 inches of mercury — the standard sea-level pressure, a number so iconic that pilots set their altimeters to it before every flight. Inches of mercury (inHg) is the pressure unit of US meteorology and aviation: it describes how high atmospheric pressure can push a column of mercury up a tube. Storm systems show up as falling numbers (a hurricane can dip below 28), and high-pressure fair weather pushes readings above 30. Meanwhile, science classes and international reports use pascals, and your car's tire gauge uses psi — same pressure, different languages.

Type your reading in the Inches of Mercury (inHg) box — start with 29.92 — and the converter translates it four ways at once: Pascals (Pa) at 3,386.38867 per inch, PSI (psi) at 0.491154 per inch, Bar at 0.03386389, and mmHg (Torr) at exactly 25.4 per inch. That last factor is beautifully simple: mercury is mercury, and an inch is 25.4 millimeters, so 29.92 inHg is 760 mmHg, the textbook standard atmosphere. Student pilots converting METAR reports, weather hobbyists with home stations, and HVAC techs reading manifold gauges all need these translations — and getting the altimeter setting wrong is genuinely dangerous, which is why aviation treats the conversion as sacred.

With the pre-filled defaults — Inches of Mercury (inHg) 29.92 — the Inhg Converter returns Pascals (Pa) 101,320.75, PSI (psi) 14.6953, Bar 1.013208, mmHg (Torr) 759.97. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.