Rigging Calculator
Estimate how much load each leg of a sling carries. The wider the legs spread, the more load each one takes, so the angle matters a lot.
- Free
- Works offline after your first visit
- Saves on this device
- No sign-up
- Updated
How it works
When the legs share the load evenly, each leg carries the total load divided by the number of legs, then divided again by the cosine of the angle from vertical. Angles are limited to 60 degrees here, because the load per leg grows very fast past that.
This shows one piece of the arithmetic only. It does not check hardware ratings, hitch types or the lift itself, and it is not a rigging plan.
Worked example
A load of 2,000 lbf on 2 legs at 30 degrees from vertical puts 1,155 lbf on each leg.
Questions
Why does a wider angle add load?
Each leg pulls at an angle, so only part of its pull lifts straight up. A wider angle means each leg must pull harder to hold the same load.
Does this replace a rigging plan?
No. A rigging plan covers hardware, ratings, angles and the lift itself, and comes from the person in charge of the lift.
Does it assume the legs are equal?
Yes. It shares the load evenly. Uneven legs or a load that shifts need a separate calculation.
More like this
- Parallel Circuit CalculatorBranch currents and total current for resistors in parallel.
- Carbon Equivalent CalculatorCarbon equivalent of a steel from its chemistry.
- NPSH CalculatorNPSH available at a pump inlet, for water.
- Amps to Watts CalculatorWatts from amps and volts, for DC or AC.
- Bend Deduction CalculatorBend allowance and deduction for sheet metal.
- Burdened Labor Cost CalculatorFull hourly cost of a worker, with taxes and benefits.