Tyre Replacement Estimator
Estimate the distance a tyre can still run before it hits the legal tread limit, from its current depth and how fast it is wearing.
Remaining tyre life
Remaining distance is (current tread − legal limit) ÷ wear rate × 1000 km. Wear is rarely perfectly linear; uneven wear, misalignment, or damage can force earlier replacement, and some heavy vehicles face a higher statutory minimum than the 1.6 mm default.
Plan tyre changes instead of reacting to them
Tyres are a major consumable on any coach or bus, and running one to the legal limit unnoticed is both a safety risk and a compliance problem. If you know a tyre’s current tread and roughly how fast it wears, this estimator turns that into a distance still to run, so you can order stock and schedule the change on your terms rather than pulling a vehicle off the road at short notice.
Track a wear rate per axle position and the estimate gets steadily more useful, giving you a realistic window for each tyre on the vehicle.
Frequently Asked Questions
How is the remaining tyre life estimated?
The tool takes the usable tread — current depth minus the legal limit — and divides it by the wear rate you enter in millimetres per 1000 km, then scales up to a distance. An 8 mm tyre with a 1.6 mm limit has 6.4 mm to give; at 0.8 mm per 1000 km that is about 8,000 km, or roughly 4,970 miles.
What legal tread limit should I use?
The default is 1.6 mm, the minimum for many cars and light vehicles across the UK and EU. Heavy and passenger-carrying vehicles can be subject to a different statutory minimum, and some operators set a higher change-out threshold as policy. Enter whatever limit applies to your vehicle and jurisdiction.
How do I find the wear rate?
Measure the tread at two points in a tyre's life, note the distance between them, and divide the tread lost by that distance to get millimetres per 1000 km. A fleet that logs tread at each inspection soon builds a reliable wear rate per axle position.
Why treat the result as an estimate rather than a deadline?
Wear is rarely perfectly linear, and it varies a lot by axle, route, and load. Uneven wear from misalignment, under-inflation, or a suspension fault — plus cuts, bulges, and sidewall damage — can force replacement long before the tread reaches the limit. Physical inspection always overrides the estimate.
Does position on the vehicle matter?
Yes. Steer, drive, and trailer or tag positions wear at different rates, so it is worth tracking a wear rate for each and running the estimate per position rather than assuming one figure covers the whole vehicle.
Estimates for planning — not professional mechanical, safety, or regulatory advice; follow the manufacturer schedule and local PSV/DOT rules.