What is the stopping distance at 30mph?

At 30mph, the total stopping distance is 23 metres (75 feet) or about 5 car lengths. This is made up of 9m thinking distance + 14m braking distance.

What is the stopping distance at 70mph?

At 70mph, the total stopping distance is 96 metres (315 feet) or about 21 car lengths. This is made up of 21m thinking distance + 75m braking distance.

How do wet roads affect stopping distance?

On wet roads, stopping distances are at least doubled. At 30mph, the stopping distance increases from 23m to at least 46m. This is because tyres have less grip on wet surfaces.

Stopping Distances Calculator

Official Highway Code stopping distances (Rule 126). Toggle between dry, wet, and icy conditions.

Based on the Highway Code — essential knowledge for your theory test

20mph

12m≈2.5 cars

30mph

14m

23m≈5 cars

40mph

12m

24m

36m≈8 cars

50mph

15m

38m

53m≈11.5 cars

60mph

18m

55m

73m≈16 cars

70mph

21m

75m

96m≈21 cars

Thinking distanceBraking distance

At 30 mph — you travel 23 metres (about 5 car lengths) before stopping. That's longer than a tennis court.

At 70 mph — you travel 96 metres before stopping. That's the length of a football pitch.

How Far Is That in Car Lengths?

Each car icon represents one car length (~4.5 metres).

20 mph≈2.5 cars

30 mph≈5 cars

40 mph≈8 cars

50 mph≈11.5 cars

60 mph≈16 cars

70 mph≈21 cars

Stopping Distance Table (Dry Road)

Speed	Thinking	Braking	Total	Car lengths
20 mph	6m (20ft)	6m (20ft)	12m (40ft)	≈2.5
30 mph	9m (30ft)	14m (45ft)	23m (75ft)	≈5
40 mph	12m (40ft)	24m (80ft)	36m (120ft)	≈8
50 mph	15m (50ft)	38m (125ft)	53m (175ft)	≈11.5
60 mph	18m (60ft)	55m (180ft)	73m (240ft)	≈16
70 mph	21m (70ft)	75m (245ft)	96m (315ft)	≈21

Theory Test Tips & Mnemonics

Thinking distance shortcut

Thinking distance in feet equals the speed in mph (e.g. 30mph = 30 feet thinking distance).

Braking distance formula

Braking distance roughly follows: speed ÷ 10 × speed ÷ 10 × 2 (in feet). For example, 30mph: (3 × 3) × 2 = 18... Highway Code rounds to nearest 5, giving 20ft at 20mph, 45ft at 30mph.

Two-second rule

In good conditions, leave at least a 2-second gap between you and the vehicle in front. Double it in rain, multiply by 10 on ice.

Key Facts

Wet roads: At least double the stopping distance
Icy roads: Up to 10 times the stopping distance
Two-second rule: In good conditions, stay at least 2 seconds behind the vehicle in front
Thinking distance depends on your reaction time (speed in mph = thinking distance in feet)
Braking distance depends on road conditions, tyre condition, and brake condition

Experience stopping distances in 3D

Feel how long it takes to stop at different speeds in our realistic driving simulator.

Start Practising Free

Stopping Distances Calculator

How Far Is That in Car Lengths?

Stopping Distance Table (Dry Road)

Theory Test Tips & Mnemonics

Key Facts

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