What Is RPE in Weightlifting? The RPE Scale and Chart Explained

RPE stands for rating of perceived exertion. In weightlifting, programs commonly use a 1-10 scale tied to how many more reps you could have completed: RPE 10 means none, RPE 9 means about one, and RPE 8 means about two.

That lets you distinguish an easy 225x5 from a difficult 225x5. Log the rating with the set so you can compare effort as well as load over time.

The lifting RPE scale

Read "reps left" as reps you could have completed with acceptable technique.

Low-effort estimates are imprecise. You rarely need to distinguish an RPE 4 from a 4.5 to make a training decision. Nearer failure, half points can help describe the difference between sets.

The original Borg scale runs from 6 to 20 and is used for general exertion. A lifting program using reps-in-reserve anchors means a different scale, so check the program's definition before transferring a rating from running to lifting.

RPE and RIR describe the same set

RIR means reps in reserve. Near failure, the usual conversion is RPE = 10 minus RIR: two reps left corresponds to RPE 8, three left to RPE 7. At easier efforts, treat the categories more loosely.

A prescription of "five reps @8" asks for five reps with about two left. It does not prescribe a fixed weight. Choose a load from recent sessions and adjust after the warm-up if needed.

ChatRPE accepts explicit RPE or RIR in a log. "Two reps left" conveys more useful information than "hard." If you only know it was difficult, record that uncertainty rather than forcing a precise score.

What a rating is worth in weight

A rating on its own does not tell you what to load. The RPE chart is the bridge: find the reps you plan to do, read across to the effort you are aiming for, and it returns roughly what percentage of your one-rep max that combination costs.

Every cell runs the same arithmetic: add the reps you completed to the reps you left, then look up what that many reps to failure is worth. Five at RPE 8 is seven reps of capacity, so it lands on the same 81% as a set of seven taken to the limit.

Reading it forward picks a load. Your program says five at RPE 8 and your best squat is 400 lb, so 81% puts the opening guess near 325 lb. That is a guess to test in the warm-ups rather than a prescription. If 325 arrives at a 9, the day has told you something the chart could not.

Reading it backwards estimates a max, which is the part a rep calculator cannot manage. Squat 315 for five, call it an 8, divide by 0.81, and you get about 390 lb. The Epley formula reads that same set as 368, because weight and reps are all it has and it cannot see the two reps you kept. Count those reps first and the formula agrees with the chart.

These are the conventional percentages popularized by Mike Tuchscherer's Reactive Training Systems, rounded here to whole numbers. Published charts disagree by a point or two, which is smaller than the error in the rating itself. RTS recommends building your own chart from tested rep maxes and keeping a separate one per lift, since rep capacity at a given percentage is not the same for a deadlift as for a bench press. Treat the table as a starting point your own logged sets correct.

What RPE to train at

Most working sets in strength programs land between RPE 7 and 9, one to three reps short of failure. Where in that band depends on what the set is for.

For strength, you rarely need to grind. A 2024 series of meta-regressions pooling proximity-to-failure studies found strength gains were similar across a wide range of reps in reserve. Heavy work at RPE 7-8, with an occasional 9 on a top set, gives you practice with heavy loads without stacking up maximal efforts.

For muscle size, the same analysis found growth increased as sets ended closer to failure. It is exploratory, since most studies' reps in reserve had to be estimated afterwards, and an earlier meta-analysis found no clear advantage for going all the way to failure over stopping just short. A common way to apply both is RPE 8-9 on squats, presses and pulls, and 9-10 on isolation work such as curls or lateral raises, where a missed rep is no safety problem.

Beginners tend to think they have more left than they do: in the study covered below, novices called a true max a 9. While you are learning a lift, stop most sets with two to four reps clearly left (RPE 6-8) and treat each rating as practice. An occasional set to failure on a machine or isolation exercise, where failing is safe, shows you what a true 10 feels like.

Rate the set you just completed

Ask how many more repetitions you could have done with similar technique. Breathlessness and discomfort can make a set feel harder without putting you as close to muscular failure as you think.

Accuracy is not uniform across the scale, and knowing where it degrades is what keeps the chart above honest. Ratings hold up best near failure and in lifters with experience: in the study that introduced the reps-in-reserve scale, experienced squatters rated a true one-rep max at 9.8 on average, while novices called that same maximal single a 9.0. The review that followed it advises against relying on the scale for lighter work several reps from failure, where the estimate is close to guesswork.

That is the practical reason a working-set rating carries weight and an RPE 4 on a warm-up does not. Consistent logging helps you compare your estimates with later performance. Bar speed can provide context, but speed alone is not a precise RPE measurement.

Record the rating promptly. A note such as "last rep slowed; another two looked possible" is useful even if you are unsure whether the set was a 7.5 or an 8. Use safe setups and coaching when learning your limits rather than testing failure on an unfamiliar heavy lift.

Use effort to adjust a load

When a set misses its target, the chart says roughly how far to move. Around five reps, one RPE point is worth two or three percent of your max: 79% at RPE 7, 81% at 8, 84% at 9. If the 325 lb five from the example above was meant as an 8 and came in at a 9, the gap is about 3% of the 400 lb max, or 12 lb, so take 10 to 15 lb off the next set. A miss by two points says more about the day than the load, and can be a reason to trim the remaining sets as well.

Across weeks, the same comparison shows progress. If 185x8 was RPE 9 several weeks ago and is repeatedly around RPE 7 now, the same work is becoming easier. If effort rises across several comparable sessions, investigate recovery and the training dose before automatically adding weight.

The deload guide covers those recovery signals. The progressive overload guide explains how to decide between adding load, adding reps, or repeating a prescription.

If you follow a program, its targets win over the ranges above. The powerlifting guide applies effort targets across a meet cycle.

Keep effort attached to the set

"Squats 275 lb for 3x5. First two sets around RPE 7, last set 8.5 because my brace became difficult to hold. Save it and compare with my previous squat sessions."

ChatRPE keeps the reported effort alongside weight and reps. Ask for matched-load comparisons or an effort chart, specifying the lift and period. A session-level note alone cannot tell you which set the rating belongs to.

The workout logging guide covers recording and correcting those entries. To use the ratings for today's prescription, see RPE-based training in ChatRPE.