Pressure Converter
Convert values between Pascal, Kilopascal, PSI, Bar, Atmosphere, Torr, and more. Visualise equivalents in real time.
Quick Calculator
Converted Result
1 atm
All Pressure Equivalents Grid
See how your entered value translates across all major pressure scales simultaneously:
What is pressure and how do we measure it?
At its core, pressure is the amount of force applied perpendicular to a surface area. In standard equations, it is written as P = F/A. But in the real world, how we measure pressure depends entirely on the context. If you are inflating a car tire, you probably think in PSI. If you are watching a hurricane build up on the weather news, you will hear meteorologists talk about millibars or inches of mercury. If you are doing laboratory physics, it is all about Pascals or Torr.
Understanding the different pressure units
The SI unit for pressure is the Pascal (Pa), defined as one Newton per square meter. Because one Pascal is a tiny amount of pressure (comparable to a single dollar bill lying flat on a table), we frequently use Kilopascals (kPa) orMegapascals (MPa). When it comes to imperial systems, PSI (pounds per square inch) is the standard. For everyday atmospheric benchmarks, we use Atmospheres (atm), where 1 atm is the normal air pressure at sea level. To put things in perspective, 1 atm is exactly 101,325 Pascals, 1.01325 bar, or about 14.696 PSI.
Why are weather forecasters using inches of mercury?
Historically, pressure was measured using liquid columns. A traditional barometer contains a column of mercury (Hg) that rises and falls depending on atmospheric pressure. That is where units like Inches of Mercury (inHg) and Torr / millimeters of mercury (mmHg) come from. In standard weather conditions at sea level, the atmosphere pushes mercury up exactly 29.92 inches or 760 millimeters. This tool lets you bounce between these historical mercury scales and modern metric grids seamlessly, giving you the math behind weather readings, engineering tasks, or automotive tire calibrations in a single click.