One-Rep-Max Calculator
Enter the weight you lifted and how many reps you performed, and this calculator estimates your one-rep max (1RM) using the Epley formula — plus a ready-made table of training weights at common percentages of your max.
Training percentages
| % of 1RM | Weight |
|---|---|
| 100% | 70 kg |
| 95% | 66.5 kg |
| 90% | 63 kg |
| 85% | 59.5 kg |
| 80% | 56 kg |
| 75% | 52.5 kg |
| 70% | 49 kg |
| 65% | 45.5 kg |
| 60% | 42 kg |
How it works
The calculator uses the Epley formula, onerep max = weight × (1 + reps ÷ 30), to estimate the heaviest weight you could lift for a single rep. It then scales that estimate down to show typical training weights at 60–100% of your max.
Tip
Estimates are most accurate for sets of around 1–10 reps. For very high rep counts the formula becomes less reliable, so treat the result as a useful guide rather than an exact number.
What is the percentage table for?
Many strength programs prescribe training loads as a percentage of your 1RM — for example, "3 sets at 80%". The table converts those percentages into an actual weight for you.
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