RPE calculator
RPE calculator and RPE chart: loads from reps in reserve
RPE (rating of perceived exertion) on the reps-in-reserve scale says how close a set was to failure: RPE 8 means about 2 reps were left. Enter a set to estimate your 1RM and the load for your next set.
Plan a set by RPE
Enter a set you just did, then the set you want to do next.
Example: 100 kg × 5 at RPE 8
Estimated 1RM
120 kg
3 reps at RPE 9
110 kg
The 5 reps at RPE 8 count as a 7-rep maximum, because about 2 reps were left.
The RPE scale for lifting
The scale most lifters use ties each RPE to the reps left in the tank, so it can be checked against what actually happens in the set. It was published in 2016 and has been used in many training studies since.
| RPE | What it means |
|---|---|
| 10 | No reps left: maximum effort |
| 9.5 | No reps left, but you could have added a little weight |
| 9 | 1 rep left |
| 8.5 | 1 rep left for sure, maybe 2 |
| 8 | 2 reps left |
| 7 | 3 reps left |
| 6 | 4 reps left |
RPE chart: percentage of 1RM
Each cell is the share of your one-rep max that allows that many reps at that RPE. Reps plus reps left give the reps to failure, and the Brzycki equation turns those into a percentage (so 1 rep at RPE 10 is exactly 100%).
| Reps | RPE 10 | RPE 9 | RPE 8 | RPE 7 | RPE 6 |
|---|---|---|---|---|---|
| 1 | 100% | 97.2% | 94.4% | 91.7% | 88.9% |
| 2 | 97.2% | 94.4% | 91.7% | 88.9% | 86.1% |
| 3 | 94.4% | 91.7% | 88.9% | 86.1% | 83.3% |
| 4 | 91.7% | 88.9% | 86.1% | 83.3% | 80.6% |
| 5 | 88.9% | 86.1% | 83.3% | 80.6% | 77.8% |
| 6 | 86.1% | 83.3% | 80.6% | 77.8% | 75% |
| 7 | 83.3% | 80.6% | 77.8% | 75% | 72.2% |
| 8 | 80.6% | 77.8% | 75% | 72.2% | 69.4% |
| 9 | 77.8% | 75% | 72.2% | 69.4% | 66.7% |
| 10 | 75% | 72.2% | 69.4% | 66.7% | 63.9% |
Other charts circulating online were built from groups of lifters and may differ by a percent or two. Your own numbers matter more: if a load listed as RPE 8 feels like RPE 9 week after week, trust the bar and adjust.
How accurate is RPE?
Lifters judge reps in reserve most accurately when a set is close to failure and has 12 reps or fewer. Across 12 studies, people underpredicted the reps they had left by about one on average, and estimates made with many reps left were often off by more. That is one reason training programmes ask for RPE 7 to 9 on most working sets: it is close enough to failure to be productive and close enough to judge.
Research on how close to failure you need to train is covered in training to failure: what the research says. The short version: sets a few reps short of failure build muscle almost as well as sets to failure, with less fatigue.
Use RPE in Bodyvault
The Bodyvault workout tracker lets you log reps in reserve with every set, on your phone or Apple Watch. The plan uses it to suggest the next weight, and a stalled lift is spotted from your real sets. To turn a single set into a maximum, use the one-rep max calculator.
Privacy
The calculation runs in this page. Nothing you type is sent to a server, saved in your browser or put into the address bar; reloading the page restores the example. The site’s usual behaviour is in the privacy policy.
Questions
What does RPE 8 mean in lifting?
On the reps-in-reserve scale, RPE 8 means you finished the set with about 2 reps left.
How do I convert RPE to a percentage of 1RM?
Add the reps left (10 minus RPE) to the reps you did, then look up that many reps to failure. The chart above does this for 1 to 10 reps.
Is RPE better than percentages?
They answer different questions. Percentages prescribe a load in advance; RPE adjusts it to how you perform on the day. Many programmes use both.
Is my data saved?
No. The calculator runs in the page and sends nothing anywhere.
Sources
- Zourdos MC et al. (2016). Novel resistance training-specific rating of perceived exertion scale measuring repetitions in reserve. J Strength Cond Res 30(1):267–275.
- Helms ER et al. (2016). Application of the repetitions in reserve-based rating of perceived exertion scale for resistance training. Strength Cond J 38(4):42–49.
- Halperin I et al. (2022). Accuracy in predicting repetitions to task failure in resistance exercise: a scoping review and exploratory meta-analysis. Sports Med 52(2):377–390.
- Brzycki M (1993). Strength testing: predicting a one-rep max from reps-to-fatigue. JOPERD 64(1):88–90.