What is wheel offset?

Wheel offset (ET) is the distance in millimetres from the hub mounting face to the centre line of the wheel. Positive offset means the hub face is towards the outer edge. Most modern cars have positive offset (ET35-ET50).

What happens with lower offset?

Lower offset pushes the wheel outward from the hub. This gives a wider track and more aggressive look, but can cause rubbing on arch liners and affect handling. A 5mm offset reduction moves the wheel 5mm outward.

How much offset change is safe?

Most manufacturers recommend staying within +/- 5mm of the original offset. Beyond this, you may need wheel spacers or risk clearance issues with suspension components and brake calipers.

What does ET mean on a wheel?

ET stands for Einpresstiefe (German for insertion depth) and is the standard marking for wheel offset. You will find it stamped on the back of the wheel, e.g. ET45 means 45mm positive offset. All European wheel manufacturers use this notation.

How much can I change the offset?

A change of plus or minus 5mm from standard is generally safe. Up to 10mm may work but should be checked carefully for clearance. Changes beyond 10mm affect the scrub radius, which alters steering feel, braking stability, and can accelerate bearing and suspension wear.

CarCalcs

Wheel Offset Calculator

Calculate how different wheel offsets affect your wheel position relative to the hub.

Original Wheel

Width

Offset (ET)

New Wheel

Width

Offset (ET)

How We Calculate This

Calculates the inner and outer edge positions relative to the hub face for both original and new wheel setups.

Formula

Inner clearance = Offset - (Wheel width in mm / 2)
Outer clearance = (Wheel width in mm / 2) - Offset

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Actual figures may vary based on driving conditions, vehicle specifications, and other factors.