One-Rep Max Calculator
Estimate your one-rep max from reps and weight.
Training percentages
| % of 1RM | Load |
|---|---|
| 95% | 109.7 kg |
| 90% | 104 kg |
| 85% | 98.2 kg |
| 80% | 92.4 kg |
| 75% | 86.6 kg |
| 70% | 80.9 kg |
| 65% | 75.1 kg |
| 60% | 69.3 kg |
These are estimates from common strength formulas, not a measured max. Lift within your ability and use a spotter for heavy attempts.
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Frequently asked questions
We plug the weight you lifted and the number of reps into three well-known strength formulas — Epley, Brzycki, and Lombardi — and show each result plus their average. The averaged figure is the headline estimate; the per-formula rows let you see how much they agree.
It is an estimate, not a measured lift. Accuracy is best when the set was 1–10 clean reps taken close to failure. Above about 12 reps the formulas drift apart and the number becomes a rough guide. Form, fatigue, and the exercise also affect the real result.
Strength programs often prescribe working sets as a percentage of your one-rep max — for example, 80% for several reps. The table converts your estimated max into common percentages so you can pick a working load without doing the arithmetic each session.
No. The calculation runs entirely in your browser. The weight and reps you enter stay on this page and are never uploaded or stored on a server.
Last updated 2026-06-23.