Braking Distance Calculator

Calculate reaction distance, braking distance and total stopping distance. Compare two conditions (Scenario A vs Scenario B): road surface, tire type and temperature.

🚗 Inputs

0.7 Now: 1.00 s 1.5

⚖️ Scenario comparison

Car 1 (Scenario A)
μ:
Car 2 (Scenario B)
μ:

📌 Results

Reaction distance — A
m
Braking distance — A
m
Total stopping distance — A
m
Reaction distance — B
m
Braking distance — B
m
Total stopping distance — B
m
Change the inputs to see the difference instantly.
Tiles “at 100 km/h”
Summer tires, +10..+30°C, reaction 1.0

How does the braking distance calculator work?

This calculator estimates how many meters a car needs to come to a complete stop and splits the stopping distance into two parts: reaction distance (time until you perceive danger and press the brake) and braking distance (from braking to a full stop).

In the comparison block you can set two scenarios (A and B) with different road surface, tires and temperature. The tiles are highlighted: green means a shorter braking distance, red means a longer one.

  • Road surface affects grip (μ): dry is better, wet is worse, snow/ice are the worst.
  • Tire type changes real traction (summer/winter/studded/worn).
  • Temperature affects tire compound performance and the surface condition.

The results are approximate and intended to understand the order of magnitude. In real life ABS, brake condition, tire pressure, road slope and many other factors matter.

FAQ

Why is braking distance longer on a wet road?

Wet surfaces have a lower friction coefficient (μ). Lower μ → longer braking distance.

How do worn tires affect braking?

Worn tread reduces traction, especially on wet roads and ice — stopping distance increases sharply.

How many meters does reaction time add?

Reaction distance is calculated as v·t. At 100 km/h it’s about 27.8 m per 1 second.

Is the calculator accurate?

This is a simplified model for estimation. Real values depend on ABS, tires, brakes, surface and load.