Rating of Perceived Exertion (RPE)

The most common RPE scales are the Borg 6-20 and Category-Ratio Scales.

Borg 6-20 RPE Scale
 
Category-Ratio Scale
6 No exertion at all   0 Nothing at all
7 Very, very light   0.3  
8     0.5  
9 Very light   0.7  
10 ‘Conversational pace’   1 Very weak
11 Fairly light   1.5  
12       Weak
13 Somewhat hard   2.5  
14       Moderate
15 Hard      
16       Strong
17 Very hard   6  
18       Very strong
19 Very, very hard   8  
20     9  
      10 Extremely strong
      11  
      * Absolute maximum