🏋️One-Rep Max Calculator (1RM)
Enter a weight and how many reps you did — we will estimate your max without you having to test it.
⚕️ Results are general estimates, not medical advice. Check with a doctor before starting a new training plan.
Your best set
Estimated one-rep max
212 lb
Epley: 216 lb · Brzycki: 208 lb
| % of 1RM | Weight | Typical reps |
|---|---|---|
| 95% | 200 lb | 1–2 |
| 90% | 190 lb | 3–4 |
| 85% | 180 lb | 5–6 |
| 80% | 170 lb | 7–8 |
| 75% | 160 lb | 9–10 |
| 70% | 150 lb | 11–12 |
| 65% | 140 lb | 15+ |
| 60% | 125 lb | 15+ |
| 55% | 115 lb | 15+ |
| 50% | 105 lb | 15+ |
Estimates are most accurate from sets of 10 reps or fewer. Always use a spotter for heavy singles!
How it works
- Epley: 1RM = weight × (1 + reps ÷ 30)
- Brzycki: 1RM = weight × 36 ÷ (37 − reps)
We show both and use the average for your training table, rounded to the nearest 5 lb (or 2.5 kg).
Worked example
185 lb for 5 reps: Epley = 185 × 1.167 = 216 lb. Brzycki = 185 × 36 ÷ 32 = 208 lb. Average ≈ 212 lb, so 80% for sets of 8 is about 170 lb.
Questions people ask
Both are close for sets under 10 reps. Epley tends to read slightly higher, Brzycki slightly lower.
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Last updated September 28, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.