One Rep Max (1RM) Calculator
Estimate your 1RM from any challenging set and get training loads.
Related:
Enter Your Set
Results
Estimated 1RM
—
—
Training percentages
1RM Guide
Formulas
- Epley: weight × (1 + reps/30)
- Brzycki: weight × 36 / (37 − reps)
- Use challenging, well‑executed sets of 3–10 reps for best accuracy.
Using your 1RM
- Strength: 85–95% 1–5 reps, long rests
- Hypertrophy: 65–85% 6–12 reps, moderate rests
- Endurance: 50–65% 12+ reps, shorter rests
Tips
- Warm up thoroughly and maintain safe technique.
- Re‑test every 4–8 weeks and adjust loads gradually.
- Accessory work and sleep/nutrition support progress.
Important
Estimates are guides—listen to your body and use spotters/safeties for maximal attempts.