RPE and RIR Explained: How to Rate Your Own Effort in Training
Two numbers, one question: how hard was that set? Here's what RPE and RIR actually mean, how they map to percentage-based programming, and why learning to rate yourself accurately is one of the best ROI skills in lifting.
What is RPE and RIR?
RPE (Rate of Perceived Exertion) and RIR (Reps in Reserve) are two scales for rating how hard a strength-training set felt. They're the tools that let you auto-regulate — adjust training load to how your body actually shows up on a given day, rather than grinding through a fixed percentage that assumes you're fresh.
The ideas are complementary:
- RPE answers "how hard?" on a 1–10 scale
- RIR answers "how many reps did you leave?" as a count
They express the same underlying variable — effort proximity to failure — but from different angles. Most modern coaches use both: RPE for programming targets, RIR for in-session cueing ("one more in the tank, then rack it").
In one line: RPE is how heavy it felt; RIR is how many more you could have done. RPE 8 ≈ RIR 2.
The Zourdos RPE Scale
The most-used RPE scale in strength training comes from Mike Zourdos's 2016 research. Unlike generic 1–10 effort scales, this version is anchored to reps in reserve, making it strength-specific and testable.
| RPE | Description | RIR |
|---|---|---|
| 10 | Maximal effort. Couldn't do another rep. Bar slowed severely on the last one. | 0 |
| 9.5 | Maybe could have gotten one more with a grinder. | 0–1 |
| 9 | One clean rep left. Last rep fast but effortful. | 1 |
| 8.5 | One or two reps left. Still moving crisply. | 1–2 |
| 8 | Two reps left. Most common working-set target. | 2 |
| 7.5 | Two or three reps left. | 2–3 |
| 7 | Three reps left. Bar speed still snappy. | 3 |
| 6 | Four+ reps left. Warm-up or speed work. | 4+ |
| 1–5 | Very light. Activation work, rehab, deload. | 5+ |
The scale below RPE 7 is intentionally coarse — once you have 4+ reps left, distinguishing RPE 3 from RPE 5 is mostly guessing, and it doesn't matter for programming decisions.
RIR — The Simpler View
RIR answers exactly one question: how many more reps could you have done with good form?
That's it. No scale, no anchors, no half-points. Just a count.
RIR works well because it asks something concrete. "Was that RPE 8.5 or 9?" forces you to translate a feeling into a number. "Could I have done two more?" is a simpler question your body can actually answer.
Rule of thumb: if you're logging sets mid-workout, use RIR. If you're writing percentage targets into next week's program, use RPE. They'll agree on the target but cue differently in the moment.
Newer lifters often find RIR more honest. RPE ratings are easy to inflate — "that was an RPE 9" can become "that was brutal, maybe RPE 10" when the lifter is tired. RIR ("could I have done another?") is harder to fudge.
When to Use Each Scale
Use RPE when:
- Writing programs or reading coach-written programs — the industry standard is RPE-based
- Tracking long-term training logs (easier to compare RPE 8 sessions across weeks than count RIR manually)
- Periodizing intensity — "build up to RPE 9 by week 4" is a common cue
- Working with very submaximal or very near-max loads where RIR rounds down to 0 or up to 4+
Use RIR when:
- Coaching or self-coaching in the moment — easier to speak, easier to feel
- Teaching beginners who haven't internalized the RPE scale yet
- Close to failure work (0–3 RIR zone, where the scale is most accurate)
- Bodybuilding-style hypertrophy sets where "two more" is an honest stopping cue
Don't use either when:
- Running a pure percentage-based program like 5/3/1 Wendler — the Training Max already bakes in the autoregulation via the AMRAP sets
- Doing strict technique work at submaximal weight — RPE/RIR is irrelevant when you're practicing form
- Prescribed AMRAP sets — the point is to go to technical failure, not to estimate it
How RPE Maps to %1RM
The Zourdos research produced a chart mapping RPE + reps to a percentage of 1RM. The values below are rounded for practical programming use:
| Reps | RPE 10 | RPE 9 | RPE 8 | RPE 7 |
|---|---|---|---|---|
| 1 | 100% | 96% | 92% | 88% |
| 2 | 96% | 92% | 88% | 84% |
| 3 | 92% | 88% | 85% | 81% |
| 4 | 89% | 86% | 82% | 79% |
| 5 | 86% | 83% | 80% | 76% |
| 6 | 84% | 81% | 77% | 74% |
| 8 | 79% | 76% | 73% | 70% |
| 10 | 75% | 72% | 69% | 66% |
Reading the table: a set of 5 reps at RPE 8 should be around 80% of your 1RM. If the prescribed weight felt like RPE 8 at 5 reps but the percentage is 75%, your 1RM estimate is likely low — which is a useful programming signal.
The values work in both directions:
- Program → bar: "3 reps at 85%" should feel like RPE 8–8.5
- Bar → 1RM: "I hit 5 reps at 90 kg with RPE 8" implies 1RM ≈ 90/0.80 = 112.5 kg
Our 1RM calculator handles the math automatically from any rep-out set — enter weight and reps, get your estimated 1RM.
"The bar doesn't lie. RPE is just learning to read it."
— Mike Tuchscherer, RTS
Training Accurate Self-Rating
Rating your own effort accurately is a skill. Beginners are terrible at it — they'll rate a set as RPE 9 that was actually RPE 7, because they've never experienced a real RPE 10 and don't have reference points.
How to calibrate:
1. Take an occasional set to failure
Once every few weeks, pick a submaximal weight and actually rep out to technical failure. That gives you a true RPE 10 anchor. Next set at RPE 8 will feel different — you'll know what "2 reps left" really means.
2. Log your rating + your actual reps
Write down: "5 reps at 90 kg, felt like RPE 8." Next week, try the same weight. If you got 7 reps easily, the first set was actually RPE 6. Track the delta over a few cycles and your ratings tighten up.
3. Film your sets
Bar speed is the objective version of RPE. A rep that moves slow relative to your warm-ups is a high-RPE rep, regardless of how you felt. Compare your felt-RPE to your observed bar speed once a week.
4. Use RIR in-session, RPE in logs
"Two more and I rack it" is an honest in-the-moment cue. "This was RPE 8" is a calibrated after-the-fact label. Mixing both tightens accuracy in both directions.
Expect to be wrong for the first ~6 months. Most lifters under-rate effort until they experience real failure under load. That's normal. Keep logging.
Common Mistakes
Rating every working set as RPE 8. Some lifters default to "felt moderate, call it 8" whether it was truly 7 or 9. Force yourself to use the full scale — particularly the half-points (7.5, 8.5) when you're genuinely between integers.
Inflating RPE when tired. A set that would be RPE 8 on Monday may feel like RPE 9 on Friday. That's a recovery signal, not a strength drop. Note the felt-rating, but cross-check bar speed before changing the program.
Using RIR below 0 RIR. "That was -1 RIR, I barely missed one" is not a thing. Once you miss a rep, it's RPE 10 and you stop rating further.
Confusing "hard" with "high RPE." A set of 20 reps with light weight can feel brutal cardiovascularly but be RPE 6–7 in the strength sense (you still have 4 reps left). RPE is specifically about proximity to muscular/CNS failure, not overall session discomfort.
Not accounting for fatigue within a session. Your 3rd set of the same weight will be a higher RPE than your 1st — that's by design in most programs. The rating should climb across sets; flat RPE across sets 1–3 usually means you're not pushing.
Trying to hit exact RPE 8.0. RPE is a coarse tool. Aiming for "between 7.5 and 8.5" is realistic; aiming for exactly 8.0 is false precision.
Using RPE to decide when to stop accessory work. For strength-focused main lifts, RPE makes sense. For 15-rep hammer curls, it's noise. Just count reps and go home.
Frequently Asked Questions
What does RPE mean in strength training?
RPE stands for Rate of Perceived Exertion. In strength training it's usually the Zourdos scale: a number from 1 to 10 that describes how hard a set felt, where 10 means maximal (no reps left), 9 means one rep left in the tank, 8 means two, and so on. It's used to auto-regulate training load day-to-day.
What does RIR mean?
RIR stands for Reps in Reserve — the number of clean reps you could still complete after your working set. RIR 2 means you stopped with two good reps left. It's a simpler, more intuitive version of RPE that skips the 1–10 scale and just asks how many reps you left in the tank.
How do RPE and RIR relate?
They are two views of the same thing. RPE 10 = RIR 0, RPE 9 = RIR 1, RPE 8 = RIR 2, and so on. Below RPE 6 the RIR scale stops being useful because you have 4+ reps left and can't gauge them accurately. Many coaches use RIR for daily cueing and RPE in programming spreadsheets.
What RPE should my working sets be?
Most strength training sits between RPE 7 and 9. RPE 7–8 (2–3 reps in reserve) is the sweet spot for building volume without wrecking recovery. RPE 9 (1 rep in reserve) is reserved for heavy single-rep work or peak weeks. RPE 10 — true failure — should be rare and usually only on programmed AMRAP sets.
Can I use RPE if I am new to lifting?
RPE ratings are a learned skill. Beginners tend to underestimate effort (feeling like RPE 9 when it was really RPE 7) because they haven't experienced a true max. For the first 6 to 12 months, use percentage-based programming or fixed rep schemes; pick up RPE as a secondary signal once you have a real sense of what failure feels like.
How accurate are RPE ratings?
With practice, trained lifters rate within about 0.5 points of their actual proximity to failure. Beginners can be off by 2+ points. Accuracy improves with: (1) occasional true-failure sets for calibration, (2) logging rated vs actual reps, and (3) checking bar speed on video.
Use RPE in a Real Program
5/3/1 Wendler builds RPE-style autoregulation in automatically: the weekly AMRAP sets let you read your current effort and adjust the Training Max accordingly — no conscious RPE tagging required.
Open the 5/3/1 Wendler Calculator → Want to estimate your 1RM from an RPE-rated set? Open the 1RM calculator →- Zourdos, M.C., et al. (2016). Novel Resistance Training–Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve. Journal of Strength and Conditioning Research 30(1): 267–275.
- Tuchscherer, M. (2008). The Reactive Training Manual. Reactive Training Systems.
- Helms, E.R., et al. (2016). RPE and Velocity Relationships for the Back Squat, Bench Press, and Deadlift in Powerlifters. JSCR 30(4): 1076–1081.
- Helms, E.R., Cronin, J., Storey, A., & Zourdos, M.C. (2016). Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training. Strength and Conditioning Journal 38(4): 42–49.
- Hackett, D.A., et al. (2012). Accuracy in Estimating Repetitions to Failure During Resistance Exercise. JSCR 26(4): 985–989.