1RM Calculator
Estimate your one-rep max from a recent set: enter the weight lifted and the number of reps completed, and get your training percentages instantly.
Estimated 1RM
Epley Formula
116.7
Brzycki Formula
112.5
Average estimate
114.6
Working weights by % of 1RM
| % of 1RM | Weight |
|---|---|
| 95% | 108.9 |
| 90% | 103.1 |
| 85% | 97.4 |
| 80% | 91.7 |
| 75% | 86 |
| 70% | 80.2 |
| 65% | 74.5 |
| 60% | 68.8 |
| 55% | 63 |
| 50% | 57.3 |
These are estimates. Never attempt a true 1RM without a spotter and a thorough warm-up.
What is a 1RM?
Your 1RM (one-rep max) is the heaviest weight you can lift once with proper form. Coaches program most workouts as a percentage of this max: light percentages for technique and volume, heavy for strength. The Epley and Brzycki formulas estimate your 1RM from a submaximal set, without ever having to test a true max. Estimates are most reliable for sets of 10 reps or fewer.