How accurate are TPMS sensors?

TPMS sensor accuracy

Direct TPMS

Direct pressure sensors are generally accurate to within 1 to 2 PSI of the actual tyre pressure. They can identify which specific tyre is low and provide real-time readings.

Indirect TPMS

Indirect systems are less precise because they infer pressure from wheel rotation speed rather than measuring it directly. They may only detect larger pressure changes and may not always identify which tyre is affected.

Why manual checks are still essential

Regardless of the type, TPMS warning lights typically only activate when pressure has dropped by around 25 percent or more below the recommended level. By that point, the tyre is already significantly underinflated and potentially unsafe. Regular monthly checks with a gauge will catch smaller pressure drops much earlier, keeping your tyres in the optimal range for safety and efficiency.