One Rep Max Calculator
Estimate your one-rep max from the weight and reps of any set, with the training weights for each percentage of your max.
Estimates are most reliable up to about 10 reps.
Estimated one-rep max
94.9 kg
- Epley
- 96 kg
- Brzycki
- 92.9 kg
- Lombardi
- 95.7 kg
Lifting 80 kg for 6 reps suggests a one-rep max of about 94.9 kg.
How it's worked out
- Epley
80 × (1 + 6 ÷ 30)96 - Brzycki
80 × 36 ÷ (37 − 6)92.9 - Average94.9
Training weights
| Of max | Weight | About this many reps |
|---|---|---|
| 100% | 94.9 kg | 1 |
| 95% | 90.1 kg | 2 |
| 90% | 85.4 kg | 3 |
| 85% | 80.6 kg | 5 |
| 80% | 75.9 kg | 8 |
| 75% | 71.2 kg | 10 |
| 70% | 66.4 kg | 13 |
| 65% | 61.7 kg | 16 |
| 60% | 56.9 kg | 20 |
- Estimates, not a test. Warm up properly and use a spotter for heavy lifts.
The formulas
Epley: w × (1 + r ÷ 30) · Brzycki: w × 36 ÷ (37 − r) · Lombardi: w × r^0.1
Worked example
80 kg for 6 reps gives 96 kg (Epley), 92.9 kg (Brzycki) and 95.7 kg (Lombardi): an estimated one-rep max of about 94.9 kg.
Questions people ask
How do I calculate my one-rep max?
The Epley formula is weight × (1 + reps ÷ 30). 80 kg for 6 reps gives 80 × 1.2 = 96 kg.
How accurate is it?
Estimates are best from sets of 3 to 10 reps. Different formulas give slightly different answers, so the calculator averages three.
What weight should I train with?
Strength work often uses 80% to 90% of your max for 3 to 6 reps; muscle growth 65% to 80% for 8 to 12.
About this calculator
Formula and rules last checked 25 October 2026Written and tested by the CalculatorDex teamReport a problem