Forklift Turning Radius Inputs
Example Data Table
| Wheelbase (m) | Width (m) | Front Overhang (m) | Rear Overhang (m) | Steer Angle (°) | Safety Margin (m) | Outer Corner Radius (m) | Turning Diameter (m) | Recommended Aisle (m) |
|---|---|---|---|---|---|---|---|---|
| 1.80 | 1.20 | 0.80 | 0.40 | 70.0 | 0.50 | 2.887 | 5.774 | 6.274 |
| 2.10 | 1.35 | 0.95 | 0.45 | 65.0 | 0.60 | 3.399 | 6.799 | 7.399 |
Use example values to test page behavior and compare layout scenarios.
Formula Used
1) Base turning radius
R = L / tan(θ)
L = wheelbase, θ = effective steer angle.
2) Inner turning radius
Rinner = max(R - W / 2, 0)
W = forklift overall width.
3) Outer body radius
Router-body = R + W / 2
This estimates the body sweep around the turn center.
4) Outer front corner radius
Router-corner = √((L + F)² + (Router-body)²)
F = front overhang.
5) Tail swing radius
Rtail = √(RearOverhang² + (Router-body)²)
Useful when checking rear counterweight clearance.
6) Turning diameter and aisle estimate
D = 2 × Router-corner
Aisle Estimate = D + Safety Margin
This gives a practical circular turning allowance for planning.
This model is intended for planning and quick comparison. Manufacturer catalogs may define turning radius with different reference points.
How to Use This Calculator
- Enter the forklift wheelbase in meters.
- Enter the overall forklift width.
- Add front and rear overhang values.
- Enter the effective steer angle in degrees.
- Set a safety margin for practical site clearance.
- Click the calculate button.
- Review radii, diameter, swept width, and aisle estimate.
- Use the graph to visualize the turning sweep.
- Download CSV or PDF for reports and layout checks.
Frequently Asked Questions
1. What does turning radius mean for a forklift?
It describes the space needed for a forklift to complete a turn. Smaller turning radius usually means better maneuverability in tight aisles, loading areas, and temporary construction access routes.
2. Why does wheelbase affect the result?
A longer wheelbase generally increases the turning path. More length pushes the front corner farther outward during rotation, so the overall turning diameter and required clearance grow.
3. Why is steer angle important?
Steer angle controls how sharply the forklift can rotate. Higher effective steering angles reduce the base turning radius, which often lowers the space needed for maneuvering.
4. What is the outer front corner radius?
It is the path followed by the most exposed front corner during a turn. This value is very useful when checking walls, pallets, barriers, columns, and temporary site fencing.
5. What does tail swing radius show?
Tail swing radius estimates how far the rear body can sweep outside the core turning path. It helps prevent counterweight contact with stored materials, racks, and nearby structures.
6. Is the aisle width value exact?
No. It is a planning estimate based on turning diameter plus a safety margin. Final aisle design should also consider load size, mast position, tire slip, and manufacturer specifications.
7. Can I use this for site logistics planning?
Yes. It is useful for comparing equipment options, staging layouts, and movement corridors. Still, final approval should rely on actual equipment data and on-site clearance checks.
8. What units should I use?
This page uses meters for all length inputs and degrees for steer angle. Keep every dimension in the same unit system to avoid incorrect results.