One-Rep Max Calculator
Estimate the heaviest weight you could lift for one clean rep without testing a true max. Enter a recent set, choose Epley, Brzycki, or the average of both, then use the percentage table for workout planning.
How the formulas work
Epley uses 1RM = weight * (1 + reps / 30). Brzycki uses 1RM = weight * 36 / (37 - reps). Both are estimates, and they are generally more useful from lower-rep sets than very high-rep endurance sets.
Keep your inputs to clean reps with consistent form. If a set broke down or included forced reps, the estimate may be too high for programming.
Treat this as a training estimate, not a guarantee of what you should attempt under maximal load.
116.7 kg
112.5 kg
114.6 kg
| Percent of 1RM | Weight |
|---|---|
| 95% | 108.9 kg |
| 90% | 103.1 kg |
| 85% | 97.4 kg |
| 80% | 91.7 kg |
| 75% | 85.9 kg |
| 70% | 80.2 kg |
| 65% | 74.5 kg |
| 60% | 68.8 kg |
| 55% | 63.0 kg |
| 50% | 57.3 kg |
Use your estimate with exercise guides
A 1RM estimate is most useful when paired with repeatable technique on the same lift. Start with these common strength movements, then use the calculator again when your working sets improve.