Intersection Turning Radius Calculator

Inputs

Vehicle preset

Loads typical geometry values you can edit.

Units

Presets convert automatically when units change.

Wheelbase (m)

Distance between front and rear axles.

Max steering angle (deg)

Use manufacturer or design vehicle guidance.

Track width (m)

Center-to-center distance between rear wheels.

Front overhang (m)

Front axle to front-most point.

Rear overhang (m)

Rear axle to rear-most point.

Clearance each side (m)

Extra allowance for mirrors, driver variation, and tolerances.

Lane width (optional) (m)

Used to check if the swept path fits within a lane.

Reset

Design vehicle	Wheelbase (m)	Steering angle (deg)	Track width (m)	Front overhang (m)	Rear overhang (m)	Suggested clearance (m)
Passenger Car	2.80	35	1.60	0.90	1.00	0.25
Single Unit Truck	6.00	32	2.10	1.30	1.80	0.35
City Bus	6.20	30	2.10	1.60	2.60	0.40
Semi-Trailer (tractor geometry proxy)	3.70	35	2.00	1.50	1.70	0.45

This calculator uses a low-speed geometric “bicycle model” for steering, then adds vehicle width and overhang effects to estimate corner clearance.

Rear-axle center path radius: R = L / tan(δ)
Inner rear wheel radius: R_in,rear = R − (TW/2)
Outer front corner radius (corner at x = L + FO, y = TW/2): R_out,front = √((R + y)² + x²)
Swept path width: W = (R_out,front − R_in,rear) + 2C