PSI (Pounds Per Square Inch)
PSI is the pressure unit used in the US and UK, often shown on tyre pressure gauges and compressors.
What is PSI (Pounds Per Square Inch)?
32–36 psi is a common range for car tyres. 1 psi is about 0.069 bar. Many digital gauges switch between psi, bar and kPa. Many filling station air pumps can be set to show either bar or psi.
How it works
It measures the force in pounds acting on one square inch of area.
Why it matters for your car
Check which unit the gauge shows before inflating. A mix-up between psi and bar can mean badly under- or over-inflated tyres.
Other terms
- ABS (Anti-lock Braking System)
- ABS Reluctor Ring (Tone Ring)
- Airing Down (Lowering Tyre Pressure Off-Road)
- Blind Spot Monitoring
- Brake Assist
- Brake Bleeding
- Clutch Control
- Front Grille
- Insurance Claim (Accident Claim)
- Liftback
- Mass Air Flow Sensor (MAF)
- Overrun Brake (Trailer Inertia Brake)
- Ozone Treatment (Odour Removal)
- Secondary Air Injection
- Side Airbag
- Sunroof
- Torque Converter
- Valet Mode
- Voltage Drop Test
- Weight Distribution