How the percentage calculator works
Why programs speak in percentages
Percentage-based loading adapts to you: "5×5 at 80%" means different absolute loads for different lifters while producing the same physiological demand. It also encodes progression cleanly — the load rises only when the rep range is completed — and it autoregulates fatigue: a rough week gets the bottom of the rep range at the same percentage.
The zones and what they buy
85–95% builds maximal strength (neural, low volume). 70–80% is the hypertrophy-strength bridge where most aesthetic and athletic work lives. 60% serves speed and technique. Below that is warm-up. Programs fail when zones blur — "heavy" 8-rep sets at 85% are ego sets that injury rates price honestly.
The round-to-plates rule
Load math meets plate math: round to 5 lb (or 2.5 kg) and stop pretending the third decimal matters. The calculator pre-rounds every row. The time saved not calculating 2.35-lb increments is better spent on the rest periods the table specifies.