RPE (Rate of Perceived Exertion)
A subjective scale from 1-10 measuring how hard an exercise feels.
RPE is used in strength training and cardio to gauge intensity without external measurements. RPE 6 means you could do 4 more reps. RPE 8 means you could do 2 more. RPE 10 is absolute maximum effort. Modern powerlifting programming uses RPE to autoregulate training — if you feel strong, you lift heavier; if you feel weak, you back off. This is more effective than rigid percentages because daily readiness varies significantly based on sleep, stress, and recovery.
Try it yourself:
Open RPE (Rate of Perceived Exertion) Calculator →