Lift Radius Calculator

Enter Lift Setup Details

Boom Length (m)

Boom Angle (degrees)

Jib Length (m)

Jib Offset Angle (degrees)

Swing Center Offset (m)

Hook Block Offset (m)

Load Center Offset (m)

Crane Base Height (m)

Maximum Permitted Radius (m)

Obstacle Distance from Center (m)

Required Clearance (m)

Safety Factor for Design Radius

Example Data Table

Boom Length	Boom Angle	Jib Length	Offsets Total	Working Radius	Hook Height	Utilization
28.00 m	62.00°	6.00 m	3.00 m	19.41 m	31.75 m	92.44%
24.00 m	68.00°	4.00 m	2.10 m	13.32 m	27.57 m	74.00%

Formula Used

The calculator treats lift radius as the horizontal distance from the crane swing center to the load center. Boom and jib reach are resolved with trigonometric components, then adjusted by hook and load offsets.

Boom Horizontal Reach = Boom Length × cos(Boom Angle)

Boom Vertical Reach = Boom Length × sin(Boom Angle)

Jib Horizontal Reach = Jib Length × cos(Boom Angle + Jib Offset Angle)

Jib Vertical Reach = Jib Length × sin(Boom Angle + Jib Offset Angle)

Working Lift Radius = Boom Horizontal Reach + Jib Horizontal Reach + Hook Block Offset + Load Center Offset + Swing Center Offset

Hook Height = Crane Base Height + Boom Vertical Reach + Jib Vertical Reach

Design Radius = Working Lift Radius × Safety Factor

Radius Utilization (%) = (Working Lift Radius ÷ Maximum Permitted Radius) × 100

Clearance Margin = Obstacle Distance − Working Lift Radius − Required Clearance

Use manufacturer lift charts, site engineering controls, and approved lift plans before field execution. This calculator supports planning review, not final authorization.

How to Use This Calculator

Enter the boom length and operating boom angle from your planned crane setup.
Add jib length and jib offset angle when a jib or extension is part of the lift.
Include swing center, hook block, and load center offsets to reflect the actual load position.
Provide the maximum permitted radius from the approved lift chart or engineered limit.
Enter the nearest obstacle distance and your required clearance allowance.
Set a design safety factor for conservative planning checks.
Press the calculate button and review the result panel shown above the form.
Export the result summary as CSV or PDF for job files, reviews, or toolbox discussions.

Frequently Asked Questions

1. What does lift radius mean?

Lift radius is the horizontal distance from the crane swing center to the load center. It strongly affects chart capacity, clearance, and safe lift planning.

2. Why do offsets matter so much?

Hook, load, and swing center offsets can add several meters to the real working radius. Ignoring them can understate the actual chart position.

3. Can I use this for lifts without a jib?

Yes. Set jib length to zero and leave the jib angle at zero or any neutral value. The calculator will then use boom reach alone.

4. What is radius utilization?

Radius utilization compares the calculated working radius against your permitted planning radius. Higher percentages indicate tighter operating conditions and less margin.

5. Why is hook height included?

Hook height helps verify vertical reach, headroom, and path geometry. It is useful when checking structure clearance or confirming pickup and set elevations.

6. Does this replace the crane load chart?

No. It supports planning calculations only. Final lift acceptance must follow the manufacturer load chart, site lift plan, and competent supervision.

7. What safety factor should I enter?

Use the factor required by your engineering method, company standard, or project lift procedure. Many teams use a conservative value above 1.00.

8. Why can clearance status fail?

Clearance fails when the obstacle distance minus working radius is smaller than the allowance you entered. Increase spacing or revise the setup.