About

Pressure calculations are critical across diverse fields, from maintaining tire safety to predicting weather patterns and ensuring diver safety. A miscalculation in industrial vacuum systems (Torr to Pascal) or scuba tanks (Bar to PSI) can lead to equipment failure or catastrophic accidents. This tool provides precise conversions between metric and imperial pressure units, adhering to standard physical constants.

It features context-aware presets. The Tire Mode optimizes for automotive resolution (1 decimal), while Scientific Mode expands precision for high-vacuum applications. The underlying logic uses exact conversion factors derived from the definition of the Pascal.

Formulas

All conversions rely on the Pascal (Pa) as the base SI unit. The conversion formula for any unit x to unit y is:

P_y = P_x × k_xk_y

Where k represents the factor to convert the unit to Pascals. For example, converting Bar to PSI:

P_psi = P_bar × 100,0006,894.757 ≈ 14.5038 psi

Reference Data

Unit	Symbol	Definition (Pa)	Use Case
Pascal	Pa	1	SI Standard, Scientific
Bar	bar	100,000	Meteorology, Industrial
Pound per Square Inch	psi	6,894.76	Automotive, Hydraulics
Standard Atmosphere	atm	101,325	Diving, Chemistry
Torr (mmHg)	Torr	133.322	Vacuum Physics, Medical
Inches of Mercury	inHg	3,386.39	Aviation, US Weather

Frequently Asked Questions

Most consumer tire gauges are accurate to ±1 PSI. However, in racing or heavy load transport, a variance of 0.5 Bar can significantly alter contact patch area and thermal management. This tool allows distinct decimal precision to match your gauge"s sensitivity.

This converter handles unit magnitude only. It does not account for atmospheric offset. "Gauge" pressure (psig) is relative to ambient air, while "Absolute" pressure (psia) includes atmospheric pressure (~14.7 psi at sea level). Ensure you know which your sensor reads before converting.

Inches of Mercury (inHg) is the standard for altimeter settings in the US. Pilots set the "Kollsman window" to the local barometric pressure to ensure altitude readings are relative to sea level, not the ground.

The definition of 1 Torr is exactly 1/760 of a standard atmosphere. This results in an irrational number when expressed in Pascals (~133.322368...). This tool uses 6 decimal places for scientific calculations.