Translate effort into load
Percentage-based programs and RPE-based autoregulation are two languages for the same thing: how hard a set was relative to your max. This converter uses the well-known Tuchscherer RPE chart to translate a reps-at-RPE set into a percentage of your one-rep max, and to project that 1RM from the weight you lifted.
How it works
The Tuchscherer chart is a lookup table. Each cell answers: “if I did N reps and stopped at this RPE, what percentage of my 1RM was the bar?” RPE is read as reps in reserve — RPE 10 is a true maximum, RPE 8 leaves two reps in the tank.
percentage = chart[reps][RPE]
estimated 1RM = load / percentageFor example, 3 reps at RPE 9 sits at about 85.5% on the chart. If you moved 150 kg for that set, your projected 1RM is 150 / 0.855 ≈ 175 kg. The tool uses the published half-point RPE values, so the numbers match standard powerlifting references.
Why autoregulation matters
Fixed-percentage programs assume your maximal strength is constant from day to day. In reality, it fluctuates by several percent due to sleep quality, stress, nutritional state, and cumulative training fatigue. A program prescribing 80% of 1RM on a day when your max is 5% lower than tested means you are actually lifting at 84% of your current max — harder than intended, and harder to recover from.
RPE-based training adjusts automatically. If 5 reps at RPE 8 is your target, you load the bar to the weight where that set would feel like two reps left in the tank. On a good day that might be a heavier weight than your program would have prescribed; on a bad day, less. Both are appropriate for that day’s capacity.
Tuchscherer RPE chart — selected values
| Reps | RPE 10 | RPE 9 | RPE 8 | RPE 7 |
|---|---|---|---|---|
| 1 | 100% | 95.5% | 92.2% | 89.2% |
| 2 | 95.5% | 92.2% | 89.2% | 86.3% |
| 3 | 92.2% | 89.2% | 86.3% | 83.7% |
| 5 | 87.2% | 84.4% | 81.8% | 79.4% |
| 8 | 80.7% | 78.6% | 76.5% | — |
These values are from the widely used Tuchscherer table. Different coaches use slightly different charts; the values are consistent in general shape but may vary in specific cells.
Projecting your 1RM
When you enter the weight used, the tool divides it by the decimal percentage to project your estimated 1RM:
For a 5-rep set at RPE 8 with 100 kg, the chart shows approximately 81.8%. Estimated 1RM = 100 / 0.818 ≈ 122 kg. This projection is most accurate at higher RPEs (8–10) and lower rep ranges (1–6), where the relationship between perceived effort and actual capacity is tightest.
At higher rep ranges (8–12+) and lower RPEs, individual variation in fatigue response, form breakdown, and lactate tolerance creates more scatter around the estimate. Use the 1RM projection from high-rep sets as a rough guide only.
Calibrating your RPE
Consistent, accurate RPE ratings require practice. Two common errors:
RPE inflation (calling it harder than it is): If you consistently report RPE 9 on sets where you actually had 2–3 reps left, your 1RM projections will be systematically too low, and your training loads too light for your prescribed RPE.
RPE deflation (calling it easier than it is): The opposite — underestimating difficulty leads to training harder than intended, poor recovery, and overestimated 1RMs.
Film your sets and review bar speed to calibrate. A true RPE 10 has a very slow, grinding bar path and no technical breakdown. A true RPE 8 has smooth bar speed and two clearly available reps remaining.