Training weights by intensity
Percentages of your estimated 1RM and the reps they typically allow.
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One Rep Max Calculator
Estimate the maximum weight you could lift for a single rep from a set you have already done, and get training weights for every rep target.
Estimated one rep max
116 kg
Epley formula—
Brzycki formula—
95% (heavy triple)—
How it works
Your one rep max (1RM) is the most weight you can lift for a single repetition. Rather than testing it directly, which is risky, you can estimate it from a lighter set taken close to failure. Estimates are most accurate at 10 reps or fewer.
The formulas
Epley: 1RM = weight × (1 + reps ÷ 30)
Brzycki: 1RM = weight × 36 ÷ (37 − reps)
Brzycki: 1RM = weight × 36 ÷ (37 − reps)
Percentage guide
| % of 1RM | Reps |
|---|---|
| 100% | 1 |
| 95% | 2–3 |
| 90% | 4 |
| 85% | 6 |
| 80% | 8 |
| 70% | 12 |
Frequently asked questions
How many reps should I use for the best estimate?
Use a set of 1–10 hard reps. Beyond 10–12 reps, the estimate becomes progressively less reliable as endurance factors in.
Is it safe to test my actual 1RM?
True 1RM testing carries injury risk and should be done with a spotter, proper warm-up, and experience. Estimating avoids that risk for programming purposes.