Reps in Reserve Scale — What Each Number Means

The reps in reserve scale is a 1-to-10 rating of how close a set came to failure, published by Zourdos and colleagues and popularized in the review by Helms. Its top half counts reps; its bottom half stops trying to. Rate your own set below and see what it implies about your max.

The scale as published

Rating	Meaning
10	Maximum effort — nothing left
9	One rep left in the tank
8	Two reps left
7	Three reps left
5 to 6	Four to six reps left
3 to 4	Light effort
1 to 2	Little to no effort

Two things about this table surprise people who met the scale through a training app.

It stops counting below 7. From 10 down to 7, each step is one specific repetition. At 5 and 6 the scale gives up on that precision and hands you a range of four to six. Below 5 it abandons repetitions entirely and describes effort, because at that distance from failure the reps left are unknowable. Conversion tables built on this scale also use half-points — 7.5, 8.5, 9.5 — to fill the gaps between whole ratings near the top.

It did not start in a laboratory. A reps-in-reserve rating system appeared first in The Reactive Training Systems Manual in 2008, used in powerlifting circles; Zourdos brought it into the scientific literature and tested it against bar velocity in experienced and novice lifters.

Why the low end is unreliable

The reason the scale collapses its bottom half is measurable. When lifters performed single repetitions at 100, 90, 75 and 60% of maximum, the spread in their ratings widened at every step down: standard deviations of 0.32, 0.92, 0.97 and 1.18. Near maximum load, the body gives away its position — bar speed drops, technique frays, and the rating converges. Three reps from failure that signal is faint, and six reps from failure it is essentially absent.

That is why programs written around this scale mostly ask for ratings of 7 and above. Anything lower is being recorded, not measured.

What the numbers are used for

Sets rated 8 to 10 — zero to two reps in reserve — cover most hypertrophy and strength work. Ratings in the 5 to 6 band mark accumulation or warm-up sets. Below that, the review suggests the scale is best used as a ceiling rather than a target: if you can accurately count reps in reserve during explosive power work, the load is too heavy for the purpose.

Continue with RIR vs RPE to see how the same set gets two different numbers, or how to use reps in reserve to turn a rating into a change on the bar. The RIR calculator converts any rating into an estimated max.

This content is informational and does not replace coaching.