RIR & RPE Strength ScaleHealth

Reps in Reserve (RIR) & RPE Rate of Perceived Exertion 1RM Calculator

Calculate your estimated One-Rep Max (e1RM), load percentage, and true training intensity using the Reps In Reserve (RIR) and RPE scale (6 to 10) developed by Mike Tuchscherer (Reactive Training Systems) for autoregulated strength progression.

Calculated Result

Estimated One-Rep Max (e1RM in kg)

126.6kg

Calculator Inputs

kg
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reps
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Estimated One-Rep Max (e1RM in kg)

126.6kg

Effective Percentage of 1RM (%)

79 %

Reps in Reserve (RIR)

2 reps

Total Possible Reps

8 reps

Working Weight Lifted vs Estimated 1RM (kg)

Working Weight
100 kg(44%)
Calculated e1RM
126.6 kg(56%)

Modern powerlifting and hypertrophy autoregulation tool. Prevents excessive central nervous system burnout while ensuring optimal effective stimulus.

This tool is a mathematical wellness and fitness estimation model for general educational guidance only. The results do not constitute medical diagnosis, clinical advice, or treatment plans. Always consult a qualified physician or certified dietitian before starting any dietary regimen, exercise program, or making health decisions.

Calculation Methodology

RPE = 10 - RIR. Potential Reps to Absolute Failure = Performed Reps + RIR. Estimated 1RM (kg) = Weight Lifted * (1 + 0.0333 * Potential Reps).

Frequently Asked Questions

RPE 10 = 0 RIR (absolute failure); RPE 9 = 1 RIR (could do 1 more rep); RPE 8 = 2 RIR (could do 2 more reps); RPE 7 = 3 RIR.

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