Work out lifting index instantly with clear inputs, formula shown and shareable results.
The lifting index is load weight divided by the recommended weight limit. An index at or below one is considered safe for nearly all healthy workers; above three the task carries a high risk of low back injury for most people. Increasing frequency reduces the recommended limit sharply, so the frequency-adjusted index is often the one that matters.
Lifting index
LI = load weight / recommended weight limit
Frequency multiplier
About 0.94 at 1 lift/min, 0.84 at 4, 0.52 at 9 and 0.28 at 12
Preliminary estimate only. Manual handling risk assessment should be carried out by a competent ergonomist using the full NIOSH method.
LI = load weight / recommended weight limit. The lifting index is load weight divided by the recommended weight limit.
That the task should be engineered out: mechanical aids, load splitting, or changing the layout so the reach and height multipliers improve. Training alone does not reduce a high lifting index.
This calculator takes 3 inputs: Weight of the load, Recommended weight limit, Lifting frequency. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.