What is an RPE calculator?
An RPE calculator uses the Tuchscherer percentage chart to do two things: estimate your 1RM from any training set (given weight, reps, and RPE), and calculate the working weight you should use for any target rep and RPE combination.
RPE (Rate of Perceived Exertion) in powerlifting measures how many reps you had left at the end of a set. RPE 10 = absolute maximum, 0 reps left. RPE 8 = 2 reps in reserve. Programming by RPE rather than fixed percentages auto-regulates for daily variation in readiness, fatigue, and strength.
RPE chart — % of 1RM (Tuchscherer)
The Tuchscherer chart is the standard reference for RPE-based powerlifting programming. Values show what percentage of your 1RM corresponds to each RPE × reps combination.
| RPE | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 100% | 96% | 92% | 89% | 86% | 84% | 81% | 79% | 76% | 74% |
| 9.5 | 98% | 94% | 91% | 88% | 85% | 82% | 80% | 77% | 75% | 73% |
| 9 | 96% | 92% | 89% | 86% | 84% | 81% | 79% | 76% | 74% | 72% |
| 8.5 | 94% | 91% | 88% | 85% | 82% | 80% | 77% | 75% | 73% | 71% |
| 8 | 92% | 89% | 86% | 84% | 81% | 79% | 76% | 74% | 72% | 70% |
| 7.5 | 91% | 88% | 85% | 82% | 80% | 77% | 75% | 73% | 71% | 69% |
| 7 | 89% | 86% | 84% | 81% | 79% | 76% | 74% | 72% | 70% | 68% |
| 6.5 | 88% | 85% | 82% | 80% | 77% | 75% | 73% | 71% | 69% | 67% |
| 6 | 86% | 84% | 81% | 79% | 76% | 74% | 72% | 70% | 68% | 66% |
Source: Mike Tuchscherer / Reactive Training Systems (RTS). Columns = reps 1–10.
Running RPE scale (Borg CR10)
In running, RPE uses the Borg CR10 scale (0–10) to rate cardiorespiratory effort. Unlike strength RPE (which measures proximity to failure), running RPE measures cardiovascular and muscular fatigue during continuous exercise.
| RPE | Effort | Breathing | Training zone | Typical pace |
|---|---|---|---|---|
| 1–2 | Very light | Barely noticeable | Active recovery | Walking |
| 3–4 | Moderate | Comfortable conversation | Easy / Zone 2 | Easy run |
| 5–6 | Somewhat hard | Harder to talk in sentences | Aerobic / Zone 3 | Steady state |
| 7 | Hard | Short sentences only | Tempo / Zone 4 | Comfortably hard |
| 8–9 | Very hard | Can barely speak | Threshold | Race pace |
| 10 | Maximum | Cannot speak | VO₂max / Sprint | All-out sprint |
Frequently asked questions
How accurate is RPE for beginners?
RPE requires experience to use accurately. Beginners consistently underestimate RPE — they think they are at RPE 8 when they actually have 4–5 reps left. RPE-based programming is most valuable for intermediate and advanced lifters who have trained consistently for 1–2+ years and can reliably gauge their proximity to failure.
What is the training max and why is it 90% of e1RM?
The training max (TM) is the weight used as the reference point for calculating all working sets in a programme. Setting it at 90% of your estimated 1RM builds in a buffer that keeps training weights manageable over a full mesocycle. A TM that is too high leads to excessive fatigue and missed reps; too low and progress stalls. Jim Wendler popularised the 90% TM in his 5/3/1 programme.
How do I use this calculator for powerlifting meet prep?
In the weeks before a meet: use Mode A after your heaviest training sets to track your e1RM trend. If your e1RM is rising at the same RPE, you are getting stronger. For opener selection, take your best training e1RM and multiply by 0.90–0.93 for a confident opener. Use Mode B with that opener weight to find your RPE — it should feel like RPE 7–7.5 on meet day.