💨 Pressure & Force
Atmospheric, mechanical, and fluid pressure measurements.
Atmosphere (atm)
A standard pressure unit defined relative to average air pressure at sea level.
101,325 Pascals
Bar
A non-SI metric unit widely used in high-pressure systems, roughly equivalent to atmospheric pressure.
100,000 Pascals
Feet of Water (ftH₂O)
A traditional plumbing unit used to describe hydraulic head pressure.
2,989.07 Pascals
Hectopascal (hPa)
The SI-conformant name for the millibar, adopted by meteorological services during metrication without altering any recorded value.
100 Pascals = 1 millibar
Inches of Mercury (inHg)
Historically used in British meteorology and aviation to measure barometric pressure.
3,386.39 Pascals
Inches of Water (inH₂O)
A fine-grained pressure unit for very low pressures, used in gas supply, flue draught and ventilation work.
249.09 Pascals
Kilopascal (kPa)
One thousand pascals, the practical metric working unit for everyday and structural pressures.
1,000 Pascals = 0.145 psi
Millibar (mbar)
Formerly standard for UK weather forecasts, numerically identical to hectopascals.
100 Pascals
Millimetres of Mercury (mmHg)
The height a column of mercury rises under a given pressure, and still the worldwide standard for reporting blood pressure.
133.32 Pascals
Pascal (Pa) - Pressure
The standard SI pressure unit representing one Newton per square metre.
1 Newton per square metre
Pounds per Square Foot (psf)
Used in older British structural engineering to describe building floor loads.
47.88 Pascals
Pounds per Square Inch (psi)
The common imperial pressure unit for everyday applications like car tyres.
6,894.76 Pascals