One Rep Max Calculator (1RM)
Estimate your one-rep max from a set of 2–12 reps with the Epley, Brzycki and Lombardi formulas, plus loads by percentage.
Estimated 1RM (average of the three)
115.5 kg
- Epley
- 116.7 kg
- Brzycki
- 112.5 kg
- Lombardi
- 117.5 kg
Estimates — test a true max only with a spotter and a proper warm-up.
Loads as a percentage of your estimated 1RM
| % of 1RM | Load |
|---|---|
| 100% | 115.5 kg |
| 95% | 109.8 kg |
| 90% | 104 kg |
| 85% | 98.2 kg |
| 80% | 92.4 kg |
| 75% | 86.7 kg |
| 70% | 80.9 kg |
| 65% | 75.1 kg |
| 60% | 69.3 kg |
| 50% | 57.8 kg |
Show the work
Epley estimate
w × (1 + reps ÷ 30)
100 × (1 + 5 ÷ 30) = 116.7 kg
Brzycki estimate
w × 36 ÷ (37 − reps)
100 × 36 ÷ (37 − 5) = 112.5 kg
Lombardi estimate
w × reps to the power of 0.1
100 × 5 to the power of 0.1 = 117.5 kg
Average the three
1RM = (Epley + Brzycki + Lombardi) ÷ 3
(116.667 + 112.5 + 117.462) ÷ 3 = 115.5 kg
How it works
Epley: 1RM = w × (1 + reps ÷ 30) · Brzycki: 1RM = w × 36 ÷ (37 − reps) · Lombardi: 1RM = w × reps^0.10 (compared in LeSuer et al., Journal of Strength and Conditioning Research 1997)
Questions
- How does the one rep max calculator (1RM) work?
- Epley: 1RM = w × (1 + reps ÷ 30) · Brzycki: 1RM = w × 36 ÷ (37 − reps) · Lombardi: 1RM = w × reps^0.10 (compared in LeSuer et al., Journal of Strength and Conditioning Research 1997).
- What do I need to enter?
- Weight lifted, Unit, Reps done. Optional fields can be left blank.
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