Calculate your one rep max for weightlifting
One rep max is the maximum weight you can lift for a single repetition with proper form. It's a standard measure of maximal strength used for programming training loads, tracking progress, and comparing strength levels.
1RM calculators are typically accurate within 5-10% when using 1-10 rep sets. Accuracy decreases with higher rep sets. Multiple formulas (Epley, Brzycki, Lander) are averaged for better estimates. Actual 1RM may vary based on individual factors.
Actual 1RM testing should be done sparingly—it's fatiguing and carries injury risk. Use calculated estimates for programming. Reserve actual testing for competitions, major milestones, or after peaking programs. Always use a spotter.
For strength: 80-90% for 3-5 reps. For hypertrophy: 65-80% for 8-12 reps. For endurance: 50-65% for 15+ reps. Periodize training through different percentages for optimal results.
Recalculate every 4-8 weeks or after completing a training program. Your 1RM changes as you get stronger. Regular recalculation ensures training loads remain appropriate for continued progress.
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