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One-Rep Max Calculator
Free one-rep max (1RM) calculator: estimate the most you could lift once from a set of 1–15 reps (Epley and Brzycki formulas), with a table of training weights from 50% to 100%.
One-rep max calculator
Estimate the most you could lift once, from a weight you lifted for several clean reps. No need to test a true max.
Estimated one-rep max
Training weights
| % of max | Weight | About this many reps |
|---|---|---|
| 100% | 75.2 kg | 1 |
| 95% | 71.5 kg | 2 |
| 90% | 67.7 kg | 3 |
| 85% | 64.0 kg | 5 |
| 80% | 60.2 kg | 8 |
| 75% | 56.4 kg | 10 |
| 70% | 52.7 kg | 13 |
| 65% | 48.9 kg | 16 |
| 60% | 45.1 kg | 20 |
| 50% | 37.6 kg | 30 |
✅ Rules last checked:
📚 Official sources: WHO: Physical activity fact sheet
We build every tool from the official rules and re-check them when they change. Always confirm with the official source before you rely on a result.
🛠️ Spotted a mistake or an out-of-date rule? Tell us
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Questions people ask
Is it accurate?+
Formulas are most accurate for sets of 2–10 reps done with good form. Treat the result as a guide.
Do I need to test my real max?+
No. Many people train from an estimated max, which is safer than lifting your heaviest possible weight.