Enter crane lift data
The page uses a single-column content flow, while inputs shift to three, two, or one columns by screen width.
Sample crane lift checks
| Lift ID | Payload | Rigging + Hook | Radius | Allowance | Effective Load | Moment | Utilization |
|---|---|---|---|---|---|---|---|
| L-101 | 18,000 kg | 1,500 kg | 16.1 m | 14% | 22,230 kg | 357.90 t·m | 85.50% |
| L-102 | 12,500 kg | 1,200 kg | 12.6 m | 10% | 15,070 kg | 189.88 t·m | 68.50% |
| L-103 | 24,000 kg | 1,700 kg | 19.3 m | 12% | 28,784 kg | 555.53 t·m | 109.00% |
Engineering logic behind the calculator
1) Gross suspended load
Gross Suspended Load = Payload + Rigging Weight + Hook or Block Weight
2) Effective load with allowances
Effective Load = Gross Suspended Load × (1 + Dynamic Factor + Wind Allowance)
3) Geometric working radius
Radius = Boom Length × cos(Boom Angle)
4) Boom tip height
Boom Tip Height = Heel Pin Height + Boom Length × sin(Boom Angle)
5) Load moment
Load Moment = Effective Load × Working Radius
6) Utilization
Utilization % = (Effective Load ÷ Rated Capacity) × 100
7) Payload allowed at target utilization
Max Payload at Target = [(Rated Capacity × Target Utilization) ÷ Allowance Multiplier] − Rigging − Hook
Practical workflow
- Select metric or imperial units before entering values.
- Enter payload, rigging, and hook or block weight.
- Provide boom length and boom angle for the planned lift geometry.
- Leave radius override empty to let the tool compute radius from geometry.
- Enter the rated capacity from the crane load chart for that setup.
- Add dynamic and wind allowances to reflect real lifting conditions.
- Set an internal target utilization for planning control.
- Press calculate to show results above the form, then review the graph and export the report.
Common questions
1) What is crane load moment?
Crane load moment is the turning effect created by the lifted load acting at a horizontal distance from the crane’s center of rotation. It helps compare demand against rated capacity for the planned radius.
2) Why does radius matter so much?
A small increase in radius can create a large increase in moment. Even when the payload stays the same, a longer reach raises overturning demand and reduces available lifting capacity.
3) Should I include rigging and hook weight?
Yes. The crane supports the full suspended load, not just the payload. Slings, shackles, spreaders, hooks, blocks, and other attached hardware should be included in the lift calculation.
4) What does the dynamic factor represent?
It accounts for added force from motion, impact, acceleration, deceleration, and operational handling. The right value depends on the lift method, site conditions, and engineering procedures.
5) Can I rely only on this calculator?
No. It is a planning tool. Final lift approval should always use the manufacturer load chart, approved lift plan, rigging study, wind limits, and site-specific engineering controls.
6) Why is there a radius override input?
Actual working radius may come from site measurements or a lift study. The override lets you use a confirmed radius instead of relying only on boom length and angle geometry.
7) What is target utilization?
Target utilization is an internal planning limit below rated capacity. Teams often use it to keep margin for uncertainty, wind, measurement error, or operational changes during the lift.
8) Why does the chart say reference only?
Real crane capacity changes with radius, boom length, configuration, outriggers, and attachments. The plotted envelope uses the entered capacity as a simple reference, not a full load chart.