One-Rep Max Calculator
Estimate your one-rep max from any set, and get a full percentage table to program your training off it.
Estimated 1-rep max
258 lb
Training percentages
| % of 1RM | Weight | Reps (approx) |
|---|---|---|
| 100% | 260 lb | 1 |
| 95% | 245 lb | 2 |
| 90% | 230 lb | 3–4 |
| 85% | 220 lb | 5–6 |
| 80% | 205 lb | 7–8 |
| 75% | 195 lb | 9–10 |
| 70% | 180 lb | 11–12 |
| 65% | 170 lb | 13–15 |
| 60% | 155 lb | 16–20 |
Estimate averages the Epley and Brzycki formulas. Accuracy is best at 1–10 reps; treat higher-rep estimates as rough.
Frequently asked
- How is one-rep max calculated?
- From a submaximal set, formulas estimate the most you could lift once. We average the Epley (weight × (1 + reps/30)) and Brzycki (weight × 36 / (37 − reps)) formulas, which agree closely in the 1–10 rep range most lifters test in.
- How accurate is an estimated 1RM?
- Very usable for programming when the test set is in the 3–8 rep range and taken near failure. Accuracy drops above ~10 reps because fatigue and technique vary more, so treat high-rep estimates as a ballpark.
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