Estimate 1RM and useful training percentages.
Estimate your one-rep max with the Epley formula: weight × (1 + reps ÷ 30). It's most accurate for sets of 10 reps or fewer.
The Epley equation estimates one-rep max from a submaximal set.
Keep your inputs consistent and compare weekly trends. Make small changes only after enough data accumulates.
Calculator results are estimates. Pregnancy, eating disorders, medical conditions, injuries, or concerning symptoms require qualified professional guidance.
Use the Epley formula — multiply the weight you lifted by (1 + reps/30). For example, 100 kg for 5 reps estimates about 117 kg.
Only with experience, a proper warm-up, and safety setup (rack, spotter). Estimating from a submaximal set is safer for most lifters.
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