RPE to RIR Conversion Calculator

Convert RPE (Rate of Perceived Exertion) to RIR (Reps in Reserve). RIR = 10 − RPE on the Tuchscherer scale.

Inputs

Result

Reps in Reserve (RIR)
1.0
RPE 9.0 = 1.0 RIR. Could have done 1 more clean rep.
  • ModeRPE → RIR
  • RPE9.0
  • RIR1.0
  • InterpretationCould have done 1 more clean rep.

Step-by-step

  1. Tuchscherer scale: RIR = 10 − RPE (clamped to 0-5).
  2. RPE 9.0 → RIR = 10 − 9.0 = 1.0.

How to use this calculator

  • Pick conversion direction.
  • Enter RPE (5-10) or RIR (0-5).
  • Use the table to plan working sets — most hypertrophy work lives at RPE 7-9 (1-3 RIR).

About this calculator

Mike Tuchscherer's RPE scale (Reactive Training Systems, ~2008) maps perceived effort to reps in reserve (RIR). The conversion is direct: RIR = 10 − RPE. RPE 10 = 0 RIR (max effort). RPE 9 = 1 RIR. RPE 8 = 2 RIR. RPE 7 = 3 RIR. RPE 6 = 4 RIR. Half-points (RPE 8.5) = "between" (1-2 RIR). Most strength programs prescribe RPE 7-9 working sets (3-1 RIR). RIR is more intuitive for newer lifters because it asks a concrete question ("how many more reps could I have done?") instead of an abstract effort rating. Both scales describe the same thing — pick whichever your coach uses.

Frequently asked

RPE was borrowed from cardio (Borg scale) and adapted for lifting. RIR is the lifting-specific reframe. RIR is easier for beginners; RPE is the lingua franca on programs.

Related calculators

More tools you might like