One-Rep Max Formulas: Epley vs Brzycki vs Lombardi
Published Apr 13, 2026 · 6 min read
Your one-rep max (1RM) is the maximum weight you can lift for a single repetition. Most lifters estimate it from a set of 3-10 reps rather than testing a true 1RM.
The Three Main Formulas
| Formula | Equation | Best For |
|---|---|---|
| Epley | 1RM = Weight Γ (1 + Reps/30) | Most popular, good for 1-10 reps |
| Brzycki | 1RM = Weight Γ 36/(37 β Reps) | Conservative, better for lower reps |
| Lombardi | 1RM = Weight Γ Reps^0.1 | Higher rep ranges (8-15) |
Example
Bench press: 185 lbs Γ 6 reps. Epley: 185 Γ (1 + 6/30) = 222 lbs. Brzycki: 185 Γ 36/31 = 215 lbs. Average: ~218 lbs.
Using Your 1RM for Training
- Strength (1-5 reps): 85-100% of 1RM
- Hypertrophy (6-12 reps): 65-85% of 1RM
- Endurance (12-20 reps): 50-65% of 1RM
- Training max: Use 90% of your estimated 1RM for programming
Try it: Use our One-Rep Max Calculator to estimate your 1RM with multiple formulas.