The technical atmosphere — "at", also written kgf/cm² — is the pressure unit of old European engineering: one kilogram of force pressing on each square centimeter. It sits just a whisper below the standard atmosphere, and the exact bridge is 98,066.5 pascals per at. Enter 1 in the Technical Atmospheres (at) box and the converter reports 98,066.5 Pascals (Pa), 0.980665 Bar, 14.22334 PSI, and 0.967841 Physical Atmospheres (atm). That last figure is the one that causes the confusion: the technical atmosphere is about 3.2% smaller than the standard atmosphere, close enough to mix up in conversation but far enough to matter in a pressure vessel calculation. Vintage machinery nameplates, old German and Russian engineering texts, and classic car manuals quote at, while modern replacements speak bar — and since 1 at is nearly 1 bar (0.980665), many shops treat them as interchangeable until precision demands otherwise. The PSI box translates it all for American gauges: about 14.22 PSI per at.

With the pre-filled defaults — Technical Atmospheres (at) 1 — the Technical Atmosphere Converter returns Pascals (Pa) 98,066.50, Bar 0.980665, PSI 14.2233, Physical Atmospheres (atm) 0.967841. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.