Strength Tool

One Rep Max Calculator

Enter any lift. Get your true 1RM using 5 validated formulas — plus a full training percentage breakdown.

Your Lift
×
5 reps
15101520
Estimated 1RM
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Enter your weight and reps above to calculate your 1RM.

Training Percentages

Your training table will appear once you enter a lift above.

Training Zones
Maximal Strength
90–100% · 1–3 reps
Pure neural drive and maximal motor unit recruitment. Builds peak force production.
💪
Strength
80–90% · 3–5 reps
Strength with some hypertrophy stimulus. Ideal for powerlifting and strength blocks.
🔵
Hypertrophy
60–80% · 6–15 reps
Optimal tension-time for muscle growth. The bread-and-butter range for bodybuilding.
🟢
Endurance
50–60% · 15–20+ reps
Muscular endurance, aerobic capacity, and fatigue resistance. Ideal for conditioning.