What percentage of 1RM does your RIR correspond to?
RIR is the reps you have left in the tank when the set ends. Converting it to a percentage of 1RM needs both numbers: how many reps you did and how many you left. A set of 5 with 2 RIR means you could have done 7, and that lands around 81% of 1RM. The short rule: add reps and RIR together, then read that total off the percentage table. Each extra RIR drops the load by roughly 3 to 4 percentage points.
The formula
Equivalent reps = reps performed + RIR. That total is how many reps you could have done to failure, and it is what you read off the %1RM table. Using Epley inverted: %1RM = 1 / (1 + equivalent reps / 30). A set of 5 with 2 RIR is 7 equivalent reps, so 1 / (1 + 7/30) = 81%.
What each variable means
- Reps performed
- The ones you completed with valid technique in the set.
- RIR
- The ones you felt you had left. It is a subjective estimate and it improves with practice: beginners systematically underestimate their RIR, meaning they leave more in the tank than they think.
Precomputed values
| Reps performed | 0 RIR | 1 RIR | 2 RIR | 3 RIR | 4 RIR |
|---|---|---|---|---|---|
| 1 | 100% | 94% | 91% | 88% | 86% |
| 3 | 91% | 88% | 86% | 83% | 81% |
| 5 | 86% | 83% | 81% | 79% | 77% |
| 8 | 79% | 77% | 75% | 73% | 71% |
| 10 | 75% | 73% | 71% | 70% | 68% |
| 12 | 71% | 70% | 68% | 67% | 65% |
Each column to the right subtracts 2 to 3 points: that is the cost, in load, of leaving one rep undone. Reading the 0 RIR row is the same as reading a classic %1RM-by-reps-to-failure table.
Run it on your numbers
How to read the result
RIR exists so you can prescribe intensity without measuring 1RM every week. Instead of writing 80%, you write 3 RIR: the load self-adjusts to the day the client had, because the same weight leaves a different RIR after a bad night's sleep. That is why autoregulation outperforms a fixed percentage over long blocks.
Assumptions and limits
- The table is a starting point, not a constant. The actual percentage someone holds at a given RIR varies by person and by lift.
- It depends on the lift: squats and deadlifts sustain more reps at the same percentage than a bench press does.
- Estimated RIR is subjective and gets more accurate with training. Close to failure (0-2 RIR) people are fairly good; at 4+ RIR the estimate degrades.
- Very long sets break the equivalence: past 12 equivalent reps the conversion loses practical meaning.
