1RM (One Rep Max) Calculator
Estimate the maximum weight you can lift for a single repetition (1RM) using your performance with lighter weights, without actually testing your limits.
kg
Estimated 1RM
~115 kg
Epley117 kg
Brzycki113 kg
Lombardi117 kg
O'Conner113 kg
Percentage Table
| % (Percent) | Approx Weight | Approx Reps |
|---|---|---|
| 100% | 115 kg | ~1 |
| 95% | 109 kg | ~2 |
| 90% | 104 kg | ~4 |
| 85% | 98 kg | ~5 |
| 80% | 92 kg | ~6 |
| 75% | 86 kg | ~8 |
| 70% | 81 kg | ~10 |
| 65% | 75 kg | ~11 |
| 60% | 69 kg | ~12 |
About
Pushing your limits with extremely heavy weights carries injury risks. This calculator predicts your 1RM based on your safe reps.
How to use
- 1. Enter the weight you lifted.
- 2. Specify how many reps you performed with that weight.
- 3. Review your percentage training zones.
Frequently Asked Questions
- What is 1RM used for?
- In training programs, weights are usually prescribed as a specific percentage (e.g., 75%, 85%) of your 1RM.
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