Sling Angle Load Calculator

Work out sling angle load instantly with clear inputs, formula shown and shareable results.

About Sling Angle Load Calculator

Sling tension is the share of the load divided by the sine of the angle from the horizontal, so tension grows without limit as the slings flatten: at 30 degrees each leg carries twice its share. The cosine component squeezes the load horizontally, which can crush a fabricated item long before the slings themselves fail.

Formulas

Leg tension

Tension = (load / number of legs) / sin(angle from horizontal)

Horizontal force

Squeeze = tension x cos(angle)

Worked example

With the default values below, Sling Angle Load Calculator returns Tension in each leg of 1,154.7. Change any input above and every figure here is recalculated in your browser.

Inputs used

Load massminimum 0 kg: 2,000 kg
Number of sling legsminimum 1: 2
Sling angle from the horizontalaccepts 5–90 °: 60 °

Results

Tension in each leg: 1,154.7 kg
Load factor from the angle: 1.1547
Horizontal squeeze on the load: 577.4 kg
Assessment: Acceptable sling angle

Step by step

1Values used
2Leg tension
3Horizontal force
4Tension in each leg= 1,154.7 kg
5Load factor from the angle= 1.1547
6Horizontal squeeze on the load= 577.4 kg
7Assessment= Acceptable sling angle

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preliminary estimate only. Lifting accessory selection must follow the manufacturer's rating tables and be planned by a competent person.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Preliminary estimate only. Lifting accessory selection must follow the manufacturer's rating tables and be planned by a competent person.

Frequently Asked Questions

How is the Sling Angle Load figure worked out?

Tension = (load / number of legs) / sin(angle from horizontal). Sling tension is the share of the load divided by the sine of the angle from the horizontal, so tension grows without limit as the slings flatten: at 30 degrees each leg carries twice its share.

What is the minimum acceptable angle?

Standards generally set 30 degrees as an absolute minimum and recommend not less than 45, with 60 degrees preferred. Below 30 degrees the loads become unmanageable.

What values do I need to enter?

This calculator takes 3 inputs: Load mass, Number of sling legs, Sling angle from the horizontal. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.