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One-rep max calculator
Enter the weight and reps from a set taken close to failure. Both formulas below are curve fits to real lifting data — expect them to agree closely under 8 reps and drift further apart past that.
Unit
Epley formula
117 kg
Brzycki formula
113 kg
Average estimate
115 kg
| Reps | Weight | % of max |
|---|---|---|
| 1 | 114.5 kg | 100% |
| 2 | 107.5 kg | 94% |
| 3 | 104 kg | 91% |
| 4 | 101 kg | 88% |
| 5 | 98 kg | 86% |
| 6 | 95.5 kg | 83% |
| 7 | 93 kg | 81% |
| 8 | 90.5 kg | 79% |
| 9 | 88 kg | 77% |
| 10 | 86 kg | 75% |
| 11 | 84 kg | 73% |
| 12 | 82 kg | 71% |
This is the same maths your plan runs on
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