Maker & Reference
Rope Working Load Calculator
Working Load Limit (WLL) = breaking strength ÷ safety factor. Manila and natural fibers need 10:1, synthetics 5-7:1.
Working load (lb)
—
- Breaking strength (lb)
- —
- Recommended SF
- —
- Per meter strength
- —
FAQ
Why bigger SF for natural fiber? +
Manila and sisal lose strength as they age + get wet. 10:1 safety factor accounts for unpredictable degradation.
Climbing / life-safety SF? +
Always 10:1 or higher. Climbing UIAA standard is 22 kN minimum breaking with dynamic absorption capacity.