Tools
RPE calculator
Enter the weight on the bar, the reps you did and how many you had left. The calculator adds the reps left to the reps done, puts that count through the Epley formula and gives the one-rep max the set implies. With nothing left it gives the same max as the one-rep max calculator. It is an estimate from a formula, and it gets rougher above about 10 reps to failure.
Estimated one-rep max
123.3kg
81.1% of your max, by the Epley formula
An estimate from a formula, not a tested number. Your own log beats any chart.
100 kg for 5 reps at RPE 8, with 2 reps left, sits at about 81.1% of a one-rep max by the Epley formula, which puts your max near 123.3 kg.
- Reps done plus reps left: the sum reads it as a weight you could lift 7 times with nothing left.
- The sum: 1 ÷ (1 + 7 ÷ 30) is 81.1%.
- The one-rep max calculator reads the same weight and reps as 116.7 kg, because it takes the set as lifted to the limit. The reps you had left make up the difference.
- In Masheen, a set at the top of your rep range logged at RPE 9 or lower counts as earned, so the coach adds weight next time.
20 kg bar + 51.25 kg per side
The bar is drawn at 122.5 kg, the nearest weight you can load to that max.
The whole chart
Reps down the side, RPE across the top. Each cell is a percentage of your one-rep max with the nearest loadable weight under it. Ringed cells call for the same percentage as your set.
| RPE | 10 | 9.5 | 9 | 8.5 | 8 | 7.5 | 7 |
|---|---|---|---|---|---|---|---|
| 1 rep | 100%122.5 | 95.2%117.5 | 93.8%115 | 92.3%115 | 90.9%112.5 | 89.6%110 | 88.2%110 |
| 2 reps | 93.8%115 | 92.3%115 | 90.9%112.5 | 89.6%110 | 88.2%110 | 87%107.5 | 85.7%105 |
| 3 reps | 90.9%112.5 | 89.6%110 | 88.2%110 | 87%107.5 | 85.7%105 | 84.5%105 | 83.3%102.5 |
| 4 reps | 88.2%110 | 87%107.5 | 85.7%105 | 84.5%105 | 83.3%102.5 | 82.2%102.5 | 81.1%100 |
| 5 reps | 85.7%105 | 84.5%105 | 83.3%102.5 | 82.2%102.5 | 81.1%100 | 80%97.5 | 78.9%97.5 |
| 6 reps | 83.3%102.5 | 82.2%102.5 | 81.1%100 | 80%97.5 | 78.9%97.5 | 77.9%95 | 76.9%95 |
| 7 reps | 81.1%100 | 80%97.5 | 78.9%97.5 | 77.9%95 | 76.9%95 | 75.9%92.5 | 75%92.5 |
| 8 reps | 78.9%97.5 | 77.9%95 | 76.9%95 | 75.9%92.5 | 75%92.5 | 74.1%92.5 | 73.2%90 |
same percentage as your set
Every figure is 1 ÷ (1 + reps to failure ÷ 30), the Epley formula, where reps to failure is reps done plus reps left. One rep at RPE 10 is 100%. These are estimates from a formula, and they get rougher above about 10 reps to failure.
RPE to reps in reserve
RPE and reps in reserve are one scale read from two ends. Reps in reserve counts the reps you had left when you stopped. RPE is 10 minus that number.
The table is the scale built for lifting by Zourdos and colleagues, as reprinted by Helms and colleagues. Masheen shows the same pairs for RPE 10 to 7 where you log a set, and counts RPE 6 as 4 reps left.
| RPE | Reps in reserve | What it means |
|---|---|---|
| 10 | 0 | Maximum effort: no more reps |
| 9 | 1 | One more rep was there |
| 8 | 2 | Two more reps were there |
| 7 | 3 | Three more reps were there |
| 5 to 6 | 4 to 6 | Four to six more reps were there |
| 3 to 4 | not counted | Light effort |
| 1 to 2 | not counted | Little to no effort |
Half points sit halfway between two rows. This page counts RPE 9.5 as half a rep left, 8.5 as one and a half and 7.5 as two and a half.
Where the percentages come from
Every percentage on this page comes from one rule, in two steps. First: reps to failure = reps done + reps left in the tank. RPE 10 is 0 left, 9 is 1, 8 is 2 and 7 is 3. A half point sits halfway, so RPE 9.5 is half a rep left.
Second: percentage of one-rep max = 1 ÷ (1 + reps to failure ÷ 30). That is the Epley formula, the one the Masheen app and the one-rep max calculator on this site use, turned round to give a share of the max. One rep at RPE 10 is the max itself, so it is 100%.
Take 5 reps at RPE 8. Two reps were left, so the set counts as 7 reps to failure, and 1 ÷ (1 + 7 ÷ 30) is 81.1%. No figure is looked up in a table: the chart, the load, the max a set implies and the print sheet are all this sum.
These figures are estimates from a formula, not measurements of you. They get rougher above about 10 reps to failure. Published RPE charts exist and give similar figures; one is in the paper by Helms and colleagues listed under Sources.
Your own log beats any chart. If a set is easier or harder than the RPE you aimed for, the set is right and the chart is off for you on that lift.
Why different sets share a percentage
Read the chart along its diagonals and the same figure repeats. Five reps at RPE 8, six at RPE 9 and seven at RPE 10 are all 81.1%. Each is seven reps to failure: 5 + 2, 6 + 1 and 7 + 0.
That is why the page rings the cells that match your set. Each ring is another way to use the same load.
When to trust a rating
A rating is a guess about reps you did not do. Helms and colleagues report a study in which lifters' guesses matched their real reps left closely in the bench press and the squat, and got better as the sets came closer to failure.
Far from failure the guess is weak. The same authors advise against judging reps left on light, fast sets.
Experience counts. They report that experienced lifters rated a true one-rep max nearer to 10 than novices did. To check your own ratings they suggest a test: rate a set stopped short, then take a set with the same weight to failure and compare.
How the load is rounded
The page takes the percentage of your max and moves it to the nearest weight you can build: the bar plus pairs of plates. With plates down to 1.25 kg that is a step of 2.5 kg; with plates down to 2.5 lb it is a step of 5 lb. A figure exactly between two loads goes to the lower one, as it does in the app.
Starting from a set instead of a max, the page multiplies the weight by 1 + reps to failure ÷ 30. With nothing left that is the sum the one-rep max calculator does, so both pages give the same max for the same weight and reps. Masheen itself estimates a one-rep max from weight and reps with the Epley formula, and does not take RPE into account.
What Masheen does with an RPE
Masheen does not set loads from a percentage chart. It uses RPE for one decision: whether a set earned more weight.
Its coach uses double progression. You build reps to the top of your range, then add weight. If you log an RPE, a set at the top of the range counts as earned when the RPE is 9 or lower, which is at least one rep left. Above that the coach has you repeat the weight before it adds more.
The same chart, the other way round
- RPE and reps in reserve chart. Start from your one-rep max and get the load for any reps and RPE.
Sources
Read on 12 November 2026.
- One-repetition maximum. Wikipedia. The Epley formula written as weight × (1 + reps ÷ 30). Every percentage on this page is worked out from it.
- Helms ER, Cronin J, Storey A, Zourdos MC. Application of the repetitions in reserve-based rating of perceived exertion scale for resistance training. Strength and Conditioning Journal, 2016; 38(4): 42–49. Further reading. The scale of RPE against reps in reserve, and what the authors report on how well lifters judge reps left. The paper also prints a chart of percentages by reps and RPE; this page does not use or reprint it.
Questions
What is RPE in lifting?
RPE stands for rating of perceived exertion: a score from 1 to 10 for how hard a set was. On the scale built for lifting, 10 is a maximum effort, 9 means one more rep was there, 8 means two more and 7 means three more.
How do you convert RPE to reps in reserve?
Take the RPE away from 10. RPE 9 is 1 rep in reserve, RPE 8 is 2 and RPE 7 is 3. Lower than that, the published scale stops counting single reps: 5 to 6 means 4 to 6 reps left, and below 5 it describes effort in words.
What percent of my one-rep max is 5 reps at RPE 8?
About 81 percent by the sum this page uses. Five reps with two left count as seven reps to failure, and the Epley formula puts a weight you can lift seven times at 1 ÷ (1 + 7 ÷ 30), which is 81.1 percent. For a 100 kg max that is 81 kg. It is an estimate from a formula, so start there and let your own sets correct it.
How accurate is counting reps in reserve?
Closer near the limit than far from it. In one study, as reported by Helms and colleagues, lifters' guesses and their real reps left were closely related, and the guesses got better as sets came nearer to failure. Experienced lifters rated more accurately than novices.
Is reps in reserve the same as training to failure?
No. Failure is 0 reps in reserve, which is RPE 10. Reps in reserve counts how many reps short of that you stopped, so 2 reps in reserve means you ended the set with two more in you.
Is RPE useful for beginners?
As a habit, yes; as the only guide to load, not yet. Helms and colleagues advise novice lifters to record reps in reserve beside their normal training numbers, and to set loads by it only once their ratings have proved accurate.