RPE calculator: estimated 1RM, RIR and the RPE chart
Put in one set — the weight, the reps and how hard it felt — and see the 1RM it implies, how many reps you had in reserve and what to load for any other rep count at the same effort. The chart underneath is the one the estimate comes from.
Your set
Estimated 1RM
Enter the weight of a set to see your estimated 1RM and the loads.
The RPE chart
Percentage of 1RM for each rep count and RPE. With a set entered, each cell also shows the load, rounded to your plates.
| RPE | RIR | Reps | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | ||
| 10 | 0 | 100.0 % | 95.5 % | 92.2 % | 89.2 % | 86.3 % | 83.7 % | 81.1 % | 78.6 % | 76.2 % | 73.9 % | 70.7 % | 68.0 % |
| 9.5 | 0.5 | 97.8 % | 93.9 % | 90.7 % | 87.8 % | 85.0 % | 82.4 % | 79.9 % | 77.4 % | 75.1 % | 72.3 % | 69.4 % | 66.7 % |
| 9 | 1 | 95.5 % | 92.2 % | 89.2 % | 86.3 % | 83.7 % | 81.1 % | 78.6 % | 76.2 % | 73.9 % | 70.7 % | 68.0 % | 65.3 % |
| 8.5 | 1.5 | 93.9 % | 90.7 % | 87.8 % | 85.0 % | 82.4 % | 79.9 % | 77.4 % | 75.1 % | 72.3 % | 69.4 % | 66.7 % | 64.0 % |
| 8 | 2 | 92.2 % | 89.2 % | 86.3 % | 83.7 % | your set: 81.1 % | 78.6 % | 76.2 % | 73.9 % | 70.7 % | 68.0 % | 65.3 % | 62.6 % |
| 7.5 | 2.5 | 90.7 % | 87.8 % | 85.0 % | 82.4 % | 79.9 % | 77.4 % | 75.1 % | 72.3 % | 69.4 % | 66.7 % | 64.0 % | 61.3 % |
| 7 | 3 | 89.2 % | 86.3 % | 83.7 % | 81.1 % | 78.6 % | 76.2 % | 73.9 % | 70.7 % | 68.0 % | 65.3 % | 62.6 % | 59.9 % |
| 6.5 | 3.5 | 87.8 % | 85.0 % | 82.4 % | 79.9 % | 77.4 % | 75.1 % | 72.3 % | 69.4 % | 66.7 % | 64.0 % | 61.3 % | 58.6 % |
| 6 | 4 | 86.3 % | 83.7 % | 81.1 % | 78.6 % | 76.2 % | 73.9 % | 70.7 % | 68.0 % | 65.3 % | 62.6 % | 59.9 % | 57.4 % |
How it works
RPE is how many reps you had left: RPE 8 means two in reserve (RIR 2), RPE 10 means none. The chart gives every set the same percentage of 1RM when reps plus reps in reserve add up to the same number — 5 reps @8, 6 @9 and 7 @10 are all seven reps to failure, and all 81.1 % of your max. That one rule is the whole table.
The estimate is only as good as the RPE you give it. Rate too low and the 1RM comes out too high, and so does every load built from it. Sets of 1 to 6 reps at RPE 7 to 9 give the steadiest numbers; above 8 reps the gaps between RPEs shrink and half a point of misjudgement moves the result more. A deadlift and a leg extension at the same RPE are not the same distance from failure either, so keep the estimate per exercise.
You never need to test a max. A top set you actually did is the input, the chart does the rest, and the loads it returns are rounded to the plates you can load. Nothing you type is stored or sent. In NoteFit the same set is written as “5 @8” in the reps field of a workout, and the plan carries the effort with the number.
Frequently asked questions
What does RPE 8 mean?
That you could have done two more reps with good form. On this scale RPE is 10 minus the reps in reserve: RPE 9 is one left, RPE 8.5 is one, maybe two, RPE 10 is a true limit set.
Is RPE 8 the same as 2 RIR?
Yes, by definition of the scale used here. RIR counts the reps left, RPE counts up from the other end; both describe the same set. Coaches who prescribe in RIR can read the chart by its second column.
How accurate is the estimated 1RM?
Close enough to load the next session from, not to call a record. Trained lifters rate their effort more accurately than beginners, low-rep sets near RPE 8 give the tightest estimates, and the number drifts with fatigue and with the exercise. Re-check it against a real top set every few weeks.
Is anything saved?
No. The calculator runs in your browser and stores nothing. The link in the address bar carries the set you entered — copy it to send it or to come back to it. To keep the plan and follow it week by week, that is what NoteFit does.
Using RIR and RPE without testing your max
Tools
Open the calculatorWeekly volume calculator: sets per muscle group
Pick the week’s exercises, set the sets and see how many sets each muscle receives — no account needed.
Training and periodization glossary
References
Work consulted for the ranges and definitions on this page. Where the honest answer is a range, it is the range these works support — not an exact number.
- Zourdos MC, Klemp A, Dolan C, Quiles JM, Schau KA, Jo E, Helms E, Esgro B, Duncan S, Garcia Merino S, Blanco R (2016). Novel resistance training-specific rating of perceived exertion scale measuring repetitions in reserve. Journal of Strength and Conditioning Research, 30(1), 267–275. doi:10.1519/JSC.0000000000001049
The study that proposed the repetitions-in-reserve rating of perceived exertion scale for resistance training.
- Helms ER, Cronin J, Storey A, Zourdos MC (2016). Application of the repetitions in reserve-based rating of perceived exertion scale for resistance training. Strength and Conditioning Journal, 38(4), 42–49. doi:10.1519/SSC.0000000000000218
How to apply that scale when prescribing training, which is the use we make of it here.