One Rep Max Calculator

Optimize your strength training with precise intensity projections.

Lift Parameters
reps
Best accuracy with 3-10 reps.
Lift Summary

Input your best set to failure. We recommend using weights you can lift for 3 to 10 reps for maximum calculation reliability.

Programming Zones
Strength85-100%
Hypertrophy70-85%
Endurance< 65%
Safety First

Never attempt a true 1RM without a qualified spotter or safety rails in place. These estimates are designed to help you train safely within your limits.

Expert Tip

Your 1RM is a "snapshot" of your strength. Factors like sleep, nutrition, and stress can shift your actual max by +/- 5% on any given day.

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