Tyre Wear Guide

Can you stop in time?

50 mph in heavy rain

How to play

You'll be driving along a wet street.
Hazards pop up. Some come into your lane, some don't.
Brake only for the ones in your way: tap Brake or press the space bar.
Your reaction time and your tyres decide whether you stop in time.

1. Choose your tyres

Or tap a tread on the board.

2. Choose your speed

How the numbers work

Braking distances come from Continental's wet braking tests on its Contidrom track (Audi A4, ContiPremiumContact tyres), presented at the ÖAMTC Symposium in Vienna in 2019: from 75 km/h a car stopped in 25 m on 8mm tread, 29 m on 4mm and 34 m on 1.6mm. From 125 km/h it took 71 m, 130 m and 199 m. We work out 50 and 70 mph between those two speeds, and 6, 5 and 3mm between the tested depths.

Thinking distance is your reaction time × your speed. Your reaction is timed from the moment the hazard starts heading into the road. The Highway Code assumes about 0.67 s (15 m at 50 mph). The hazard is placed so 1.6mm tyres only stop in time with a reaction that fast.

Checks: ADAC's 2024 test measured 28.5 m for a new Continental tyre braking from 80 km/h in the wet (we use 28.8 m at 50 mph). Auto Express measured 82 m from 70 mph in the wet on 5mm tyres (we use 83.1 m). Real cars, tyres and roads vary.

The desk guide garages use to explain tyre wear, as an interactive demo

What it is

A 3D-printed board with six real tread depths, from a new 8mm tyre down to the 1.6mm legal limit. Garages keep it on the service desk so customers can see, and feel, how worn their own tyres are.

Designed and made by Got Ideas.

Play with it

Drag a tread plate off the board and drop it back. It snaps home like the magnets on the real one.
Tap any piece to find out what it means, including the small wear block in each centre groove.
Tap the logo plate to see your own logo on the board.

The tests

20p test: push a 20p into each groove and see when the band starts to show.
Stopping distance: fit worn tyres to a car, then brake when a hazard appears. Can you stop in time?
Bonus: , from size to the date it was made.

Garages: want guides with your own logo? Tap Order guides.

Feel for the wear bar

Pick a tread, then rub across it

Every tyre has small bars across the bottom of its main grooves, set at 1.6mm: the legal limit.
Run a finger across the tread. You'll feel a step down from the tread onto the bar.
The smaller the step, the more worn the tyre. No step at all means the tread is flush with the bar: replace now.

8mm treadRub across the tread.

Order your guides

Tyre Wear Guides are made to order for garages and dealerships, in packs of 5 or more, with your own logo plate if you'd like one. Send us your details and we'll reply with a quote and delivery date.