RIR / RPE Training Load Calculator
Autoregulate your training: enter an estimated 1RM, target reps and reps in reserve (RIR) to get the percentage of 1RM and the working weight for the day.
Results
- Percentage of 1RM
- 81.1%
- 5 reps + 2 RIR = 7 effective reps
- Recommended working weight
- 97.3 kg
- Approx. RPE 8
RPE to RIR conversion
| RPE | RIR | Meaning |
|---|---|---|
| 10 | 0 | Max effort, no reps left |
| 9 | 1 | Very hard, one rep left |
| 8 | 2 | Challenging, two reps left |
| 7 | 3 | Moderate, three reps left |
| 6 | 4+ | Light, four or more reps left |
How it works & limitations
How the load is derived
This calculator treats 'target reps + RIR' as the effective rep max and applies the Epley relationship in reverse: %1RM = 100 / (1 + 0.0333 x effective reps). For example, 5 reps with 2 RIR behaves like a 7-rep max, about 81% of 1RM.
Using RIR in practice
RIR autoregulates training to daily readiness: on a good day the same RPE is heavier, on a fatigued day it is lighter. Keep the RPE scale consistent, and treat percentages as a starting point - bar speed and feel refine the final load.
Sources
Last updated 2026-08-13
- Epley, B. (1985). Poundage chart. Boyd Epley Workout, Lincoln, NE.
- 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. Sports Medicine, 46(4), 513-524.
An estimate for autoregulated training. The RPE/RIR scale requires honest effort perception; a spotter or video review helps calibrate it.
Frequently asked questions
What is RIR (reps in reserve)?
RIR is how many more clean reps you could have performed at the end of a set. RPE 10 means 0 RIR (failure), RPE 9 means about 1 RIR, RPE 8 means about 2 RIR. Using RIR lets the day's readiness set the load instead of a fixed percentage.
How is the percentage calculated?
This calculator treats 'reps performed + RIR' as the effective rep max and applies the Epley relationship in reverse: %1RM = 100 / (1 + 0.0333 x effective reps). It is an estimate, so adjust from bar speed and feel.