What Is PSI?

Woman Checking Tire Pressure
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The acronym PSI stands for "Pounds per Square Inch," and is the common unit of measurement for pressure.

It can be understood as the amount of force that is exerted on an area of one square inch.

Normal atmospheric pressure at sea level is 14.7 PSI.

Pronunciation: Pronounce each letter individually: P - S - I.

Example: Normal tire pressure is usually about 32 PSI.