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One-rep max calculator
Estimate your max without testing it, then use the chart to set your working weights.
Your result
These tools give general estimates, not medical advice. If food, weight or exercise is causing you distress, a doctor or an organization such as NEDIC (Canada) or the National Alliance for Eating Disorders (US) can help.
How this works
We use the Epley formula: weight × (1 + reps ÷ 30). A single rep is treated as your actual max. Estimates are most reliable from sets of 10 reps or fewer.
Common questions
Do I need to test my one-rep max?
No. A hard set of 3 to 8 reps gives a useful estimate with less risk than a true max attempt.
How often should I recalculate?
Every 4 to 8 weeks is plenty, or whenever your working sets clearly improve.