Although during your practical test the examiner takes your speedometer as 100% accurate
and has a zero tolerance for speeding please be aware of the following.
Do Not take this as an excuse to speed.
What Speed Camera Tolerance Actually Means
Speed camera tolerance is a small margin that authorities apply before issuing a speeding fine. If the speed limit is 60 km/h and the tolerance is 2 km/h, the camera will not trigger until a vehicle passes at 63 km/h or above.
This tolerance exists for two reasons. First, all measurement devices have a small margin of error. Radar and laser systems are accurate but not perfect, and applying a buffer protects against false readings. Second, speedometers are not perfectly calibrated, so a small allowance accounts for drivers who believe they are at the limit but may be marginally over.
The tolerance is not a free speed bonus. It exists to account for measurement uncertainty, not to give you extra speed.
The Three Tolerances Every Driver Should Understand
Most drivers think there is one tolerance. There are actually three separate factors at play, and understanding all of them is the difference between staying fine-free and copping a penalty notice.
1. Speedometer Tolerance (Your Car’s Reading)
Under Australian Design Rule ADR 18/03, every car sold in Australia must have a speedometer that never reads lower than the vehicle’s true speed. Manufacturers are allowed a margin of up to 10% plus 4 km/h above the true speed, but never below it.
In practice, most car manufacturers set speedometers to read 3-7% higher than actual speed. This means:
This is why many drivers “never get caught” despite regularly showing 63-65 km/h in a 60 zone. Their true speed is likely 59-61 km/h, well within or just at the limit.
Factors that affect speedometer accuracy include tyre size (worn tyres read high, larger aftermarket tyres read low), tyre pressure, and vehicle load. If you’ve changed your tyre size from the factory specification, your speedometer could be reading incorrectly in either direction.
2. Camera Calibration Tolerance (The Device’s Accuracy)
Every speed camera in Australia must be regularly tested and calibrated. The testing records confirm the device measures speed within a certified accuracy range, typically ±2 km/h for modern digital systems.
Authorities apply a tolerance margin on top of the speed limit to account for this device accuracy. This is the tolerance people usually mean when they talk about “the camera buffer.”
Camera calibration records are public documents in most states. If you receive a speeding fine, you can request the calibration certificate for the specific camera that detected you. This certificate shows when the camera was last tested and its measured accuracy.
3. Enforcement Tolerance (The Discretionary Buffer)
This is the tolerance that authorities set as policy, applied after the camera detects a speed. It is the gap between the speed limit and the speed at which a fine is actually issued.
Enforcement tolerance varies by state and camera type. Some states publish their tolerance figures. Others keep them confidential, arguing that publishing the exact number encourages drivers to speed up to the tolerance limit. Victoria is the most transparent. NSW is the least.
State-by-State Speed Camera Tolerance
The table below summarises the known tolerance figures for each state. Where the tolerance has not been officially published, we note the best available information from government statements and transport authority publications.