Tools
One rep max calculator
Your estimated one rep max is the weight times one plus the reps divided by 30 (the Epley formula). It is most accurate for sets of 10 reps or fewer.
Your result
- Estimated 1RM
- 0 kg
| % | kg |
|---|---|
| 95% | 0 |
| 90% | 0 |
| 85% | 0 |
| 80% | 0 |
| 75% | 0 |
| 70% | 0 |
| 65% | 0 |
| 60% | 0 |
| 50% | 0 |
How it works
- Epley: 1RM = weight x (1 + reps / 30). Kynetix uses the same formula to spot personal records as you lift.
- Training weights are your estimated 1RM times each percentage, rounded to the nearest 0.5 kg.
Kynetix works these out from your profile and adjusts them as you train and log. See the app.
Questions
How accurate is a one rep max calculator?
Close for sets of 3 to 10 reps, less so above 12. It estimates; it does not replace a careful test with a spotter.
What percentage of my 1RM should I train at?
Roughly 70 to 85% for most strength and muscle work, which lines up with sets of about 5 to 12 reps.
More calculators
Estimates for healthy adults, not medical advice.