One Rep Max (1RM) Calculator
Calculate your estimated one rep max using four formulas (Epley, Brzycki, Lander, Lombardi). Enter weight and reps — get a full percentage chart for programming your lifts.
Estimated 1 Rep Max
212.9
lb
Your set was at 87% intensity
Training percentages
Use this table to program sets. Based on your estimated 1RM of 212.9 lb.
| Reps | % of 1RM | Weight (lb) |
|---|---|---|
| 1 rep | 100% | 212.9 |
| 2 reps | 95% | 202.3 |
| 3 reps | 93% | 198 |
| 4 reps | 90% | 191.6 |
| 5 reps | 87% | 185.2 |
| 6 reps | 85% | 181 |
| 7 reps | 83% | 176.7 |
| 8 reps | 80% | 170.3 |
| 9 reps | 77% | 163.9 |
| 10 reps | 75% | 159.7 |
| 11 reps | 73% | 155.4 |
| 12 reps | 70% | 149 |
Need help loading those plates? Plate Calculator →
What is a one rep max?
Your one rep max (1RM) is the maximum amount of weight you can lift for a single repetition of an exercise with proper form. It's the gold standard for measuring absolute strength and is used to set training loads across most strength programs.
The four formulas explained
No formula is perfectly accurate for every person — individual factors like muscle fiber type, training age, and neural efficiency all affect how well you can convert submaximal effort to a true max. Using the average of all four formulas (shown as your primary result) gives a more reliable estimate than any single formula.
- Epley (1985): weight × (1 + reps/30). The most widely cited formula; tends to slightly overestimate at high rep ranges.
- Brzycki (1993): weight × 36 / (37 − reps). More conservative; works best in the 1–10 rep range.
- Lander: (100 × weight) / (101.3 − 2.67123 × reps). Often the most accurate in the 5–10 rep range.
- Lombardi: weight × reps^0.10. Accounts for fatigue accumulation at higher rep ranges.
How to use your 1RM for programming
The percentage table below your result maps rep ranges to training percentages. A common rule of thumb: 5 reps at ~87% (strength focus), 8 reps at ~80% (hypertrophy focus), 12 reps at ~70% (muscular endurance). Most programs, including 5/3/1, Texas Method, and Wendler, are built around percentages of 1RM.
For best results, use a rep range you can perform consistently — 3-8 reps typically yields the most accurate 1RM estimate.