One Rep Max Calculator
Never test a true 1RM cold — derive it safely from a hard set of 3–8 reps.
Estimated 1RM (Epley)
263 lb
Brzycki variant: 253 lb · O'Conner: 253 lb.
| % of 1RM | Weight | Use |
|---|---|---|
| 95% | 250 lb | Peaking |
| 90% | 237 lb | Strength |
| 85% | 224 lb | Strength |
| 80% | 210 lb | Hypertrophy |
| 70% | 184 lb | Volume |
How the One Rep Max Calculator works
The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:
Frequently Asked Questions
How does the One Rep Max Calculator work?
Enter your numbers above and results update instantly using standard formulas, computed entirely on your device.
Is the One Rep Max Calculator free to use?
Yes — completely free with no signup required, and it works on phones, tablets, and desktops.
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