Atmosphere (atm) to mmHg Converter
Enter a value to instantly convert between pressure units.
1 Atmosphere = 759.9999 mmHg
Key Formulas
Pound per Sq. Inch → Bar
bar = psi × 0.0689476Bar → Pound per Sq. Inch
psi = bar × 14.5038Atmosphere → Pound per Sq. Inch
psi = atm × 14.6959Pound per Sq. Inch → Atmosphere
atm = psi × 0.068046Formula
mmHg = atm × 760One atmosphere exactly equals 760 mmHg by historical definition — this standard was set based on Torricelli's barometer, which used a 760 mm mercury column. Medical professionals use mmHg for blood pressure readings, while vacuum scientists use the equivalent torr unit. Understanding this conversion is essential for both clinical and laboratory settings.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
Standard atmospheric pressure at sea level = exactly 760 mmHg by definition, the baseline for pressure gauges.
1 atm = 760 mmHg
A medical technician documents blood pressure at sea level with half-atmosphere back pressure = 380 mmHg baseline.
0.5 atm = 380 mmHg
A laboratory vacuum chamber operating at 2 atm (twice atmospheric) = 1520 mmHg for pressure vessel compliance testing.
2 atm = 1520 mmHg
A patient's systolic blood pressure reading of ~1007 mmHg absolute (rare condition) with atmospheric contribution.
1.325 atm = 1007 mmHg