Lifting Sling Tension Calculator
Tension per sling leg versus angle — the rigger's load chart.
At 30° each leg of a 2-leg sling carries the WHOLE load. Riggers' rule: keep the included angle under 90° (legs ≥ 60° from horizontal) and derate slings to the chart, not hope.
Formula
Lifting Sling Tension Calculator is a free sling tension for structural engineers, fabricators and site engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Lifting Sling Tension Calculator
Tension per sling leg versus angle — the rigger's load chart. The calculation implements T = W / (n·sin θ) (ASME B30.9 — slings). At 30° each leg of a 2-leg sling carries the WHOLE load. Riggers' rule: keep the included angle under 90° (legs ≥ 60° from horizontal) and derate slings to the chart, not hope.
How to use Lifting Sling Tension Calculator
- 1Enter Load weight in kg.
- 2Enter Sling legs.
- 3Enter Leg angle from HORIZONTAL in deg.
- 4Read Tension per leg, Angle factor (×vertical share) instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Lifting Sling Tension Calculator?
- ✓Implements the standard formula — T = W / (n·sin θ)
- ✓Reference cited on-page: ASME B30.9 — slings
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Built-in engineering verdict flags out-of-range results instantly
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Lifting Sling Tension Calculator use?+
It computes T = W / (n·sin θ), per ASME B30.9 — slings. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
At 30° each leg of a 2-leg sling carries the WHOLE load. Riggers' rule: keep the included angle under 90° (legs ≥ 60° from horizontal) and derate slings to the chart, not hope.
Can I use this for real structural design?+
It implements the exact textbook/code formula cited below the result and is ideal for sizing, checking and learning. Final designs should be verified by a qualified engineer against the full code with all load cases.
Is the Lifting Sling Tension Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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