Braking Distance Calculator

Estimate stopping distance from speed, grip and reaction time.

How it works

1

Enter the speed

Travelling speed in km/h.

2

Pick the grip

A friction coefficient for the surface and tyres.

3

Add reaction time

Time before you hit the brakes - we add the thinking distance.

Frequently asked questions

How is braking distance calculated?

Braking distance = v squared / (2 x mu x g), where v is speed in m/s, mu is the grip coefficient and g is 9.81. We add the thinking distance (speed x reaction time) for the total stopping distance.

Why does stopping distance quadruple with speed?

Braking distance grows with the square of speed, so doubling your speed roughly quadruples the distance needed to stop - a key reason small speed increases matter so much.

How much does wet road add?

Grip can drop from about 1.0 dry to 0.5 wet, which doubles the braking distance. Ice can cut grip to 0.1-0.2, multiplying it several times over.

Need the full ECU suite?

The desktop Softechpro Solutions software corrects checksums for 260+ ECU families and does DPF/EGR/AdBlue/DTC off, Stage tuning and DTC diagnostics offline.

See pricing — €299 one-time
×

🔒 Log in to continue

These tools are 100% free — just sign in to your Softechpro account to unlock the full result.