How to use the One Rep Max Calculator
The one rep max calculator estimates the most you could lift once from a lighter set.
Open the One Rep Max Calculator →
What you need to enter
- Weight lifted
- Repetitions
The formula
Epley: weight × (1 + reps ÷ 30). Brzycki: weight × 36 ÷ (37 − reps). Other formulas give similar results.
Worked example
Using the default values in the calculator:
- Weight lifted: 100
- Repetitions: 5
| Epley | 116.7 |
| Brzycki | 112.5 |
| Lander | 113.7 |
| Lombardi | 117.5 |
| O'Conner | 112.5 |
| Average | 114.6 |
Tips for better results
- Estimates are best for sets of 2–10 reps.
- Test with a spotter.
Common mistakes to avoid
- Using a very high rep set.
- Testing a true max without warm-up.
Please note: Health calculators and guides give general estimates, not medical advice. Talk to a doctor or other qualified professional about your own health. See our Disclaimer.