RPE Calculator | Strength Level Calculator

Q: What does RPE mean?

RPE stands for Rating of Perceived Exertion. In strength training it is usually a 1–10 rating of how hard a set felt, where 10 means you could not have done another rep. Most lifters use the upper part of the scale, from about 6 to 10.

Estimated Weight at Each RPE (table)
RPE	RIR	% 1RM	Weight (est.)

Calculate to see estimated weights for your rep count at RPE 6–10.

What Is RPE?

RPE stands for Rating of Perceived Exertion. In strength training it is a rating, usually from 1 to 10, of how hard a set felt. Lifters mostly use the top of the scale: RPE 10 means no more reps were possible, and each point below that means roughly one more rep was left.

Those leftover reps are called reps in reserve (RIR). Rating sets by RPE lets you choose loads based on how you perform on the day — for example, “5 reps at RPE 8” — instead of a fixed percentage. Because RPE is a personal judgement, every number derived from it is an approximation.

RPE rates how hard a set felt, typically on a 6–10 scale in lifting.
RIR is how many more reps you could have done — roughly 10 − RPE.
Approximate by nature. Ratings depend on experience, exercise and how close the set was to failure.

RPE and Reps in Reserve

RPE, approximate reps in reserve and general interpretation
RPE	Approx. RIR	General interpretation
6	~4	Moderate effort. The weight moves well and several more reps would be possible.
7	~3	Challenging but controlled. Bar speed is still good.
8	~2	Hard. A couple more reps would be possible before failure.
9	~1	Very hard. Probably one more rep in the tank.
10	0	Maximal effort for that weight and rep count — no more reps would be possible.

These RIR values are approximate. Half points (such as 8.5) mean “maybe one or two more reps”. How accurately people judge RIR varies, and it is usually better on sets closer to failure.

How the RPE Calculator Works

1. Estimate reps in reserve

The calculator uses the reps-in-reserve interpretation of RPE:

RIR ≈ 10 − RPE

2. Estimate reps to failure

Your set is treated as if it had been continued to failure:

Reps to failure ≈ reps performed + RIR

3. Estimate 1RM and intensity

That rep count goes into the same five formulas used by our One Rep Max Calculator — Epley, Brzycki, Lander, Lombardi, Mayhew et al. — and the average is your estimated 1RM. Training intensity is the weight lifted as a percentage of it. The table of weights at each RPE reverses the same formulas.

Training intensity = weight lifted ÷ estimated 1RM × 100%

Assumptions and limitations

The results assume your RPE rating is accurate and that the 1RM formulas fit you. In practice, lifters often misjudge reps in reserve, especially on lighter or longer sets and on unfamiliar exercises; fatigue, technique and exercise choice also affect how many reps you can do at a given weight. Use the numbers as estimates to guide load selection, not as exact performance predictions.

Sources

Zourdos, M. C., Klemp, A., Dolan, C., et al. (2016). Novel resistance training–specific rating of perceived exertion scale measuring repetitions in reserve. Journal of Strength and Conditioning Research, 30(1), 267–275.
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. Strength and Conditioning Journal, 38(4), 42–49.
Epley, B. (1985). Poundage Chart. Boyd Epley Workout. Lincoln, NE: Body Enterprises.
Brzycki, M. (1993). Strength testing — predicting a one-rep max from reps-to-fatigue. Journal of Physical Education, Recreation & Dance, 64(1), 88–90.
Lander, J. (1985). Maximums based on reps. National Strength and Conditioning Association Journal, 6, 60–61.
Lombardi, V. P. (1989). Beginning Weight Training. Dubuque, IA: W. C. Brown.
Mayhew, J. L., Ball, T. E., Arnold, M. D., & Bowen, J. C. (1992). Relative muscular endurance performance as a predictor of bench press strength in college men and women. Journal of Applied Sport Science Research, 6(4), 200–206.

Example Calculation

Example only

A lifter squats 100 kg for 5 reps and rates the set RPE 8. Illustrative figures, not a real person’s result.

RIR10 − 8 = 2
Reps to failure5 + 2 = 7 reps
Estimated 1RMAverage of five formulas for 100 kg × 7 = 122 kg
Intensity100 ÷ 122 = 82%

Once you have an estimated 1RM, you can compare it with reference levels in the Strength Level Calculator, or estimate a specific lift with the Squat Calculator, Bench Press Calculator or Deadlift Calculator. For more on the scale itself, read what RPE means in strength training.

RPE guide
What Is RPE in Strength Training?
How the RPE scale rates effort, how it relates to reps in reserve and how to use it.
Guide
What Is One Rep Max (1RM)? How to Calculate Your 1RM
What a one-rep max is, how it is estimated and how it is used to plan training.
Reference
Strength Standards
Compare an estimated 1RM with reference levels for the squat, bench press, deadlift, overhead press and barbell row.

Frequently asked questions

What does RPE mean?

RPE stands for Rating of Perceived Exertion. In strength training it is usually a 1–10 rating of how hard a set felt, where 10 means you could not have done another rep. Most lifters use the upper part of the scale, from about 6 to 10.

What is RPE 8?

On the reps-in-reserve scale, RPE 8 means you finished the set with about two reps left — you could probably have done two more before failure. It is a common target for hard but repeatable working sets.

How does RPE relate to RIR?

RIR (reps in reserve) is how many more reps you think you could have done. On the RIR-based scale, RIR is roughly 10 minus RPE: RPE 9 ≈ 1 RIR, RPE 8 ≈ 2 RIR, RPE 7 ≈ 3 RIR. Half points such as 8.5 mean “maybe one or two more”. The relationship is approximate, because it relies on your own judgement.

Is RPE 10 always a maximum effort?

RPE 10 means no more reps were possible at that weight — a maximal effort for that set. It does not necessarily mean the weight was your one-rep max: you may have been able to lift slightly more for fewer reps. Some lifters also use 9.5 for “could not do another rep, but could have added a little weight”.

How accurate is an RPE calculator?

It gives an estimate, not an exact prediction. Its accuracy depends on how well you judge your reps in reserve and on how well the 1RM formulas fit you. Research suggests lifters tend to rate effort more accurately on sets closer to failure and with more experience of using the scale.

Can RPE be used with any exercise?

RPE can be used with most exercises, but it is easiest to rate on lifts you perform often with consistent technique, such as the squat, bench press and deadlift. For less familiar movements, ratings tend to be less consistent.

How is the estimated 1RM calculated from RPE?

The calculator adds your estimated reps in reserve to the reps you performed, treating the set as if it had been taken to failure. That rep count goes into the same five 1RM formulas used by our One Rep Max Calculator, and the average is shown.

What does training intensity mean here?

Training intensity is the weight you lifted as a percentage of your estimated 1RM. For example, 100 kg with an estimated 1RM of 125 kg is 80%. It describes load, not how hard the set felt — that is what RPE describes.

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Estimated Weight at Each RPE