RPE Calculator

This RPE calculator helps you estimate your one-rep max (1RM) based on a set you've performed. Simply enter the weight lifted, number of reps completed, and your Rate of Perceived Exertion (RPE) to calculate your estimated max.

The calculator uses the Epley formula with RPE adjustments to account for reps left in reserve. Once calculated, you'll see a full RPE chart showing what weights to use for any rep/RPE combination.

RPE (Rate of Perceived Exertion) is a scale from 1-10 that measures how hard a set felt. In strength training, we typically use RPE 6-10:

• RPE 10 - Maximum effort, no reps left in the tank
• RPE 9 - Could have done 1 more rep
• RPE 8 - Could have done 2 more reps
• RPE 7 - Could have done 3 more reps
• RPE 6 - Could have done 4+ more reps

Half values (e.g., RPE 8.5) indicate you're between two levels - maybe you could have done one more rep, but it would have been a grind.

The calculator uses the Epley formula modified for RPE:

For example, if you lifted 225 lbs for 5 reps at RPE 8 (2 reps in reserve), your adjusted reps would be 7, giving an estimated 1RM of about 277 lbs.

Once you've calculated your 1RM, the chart shows recommended weights for any rep/RPE target. Use this to plan your training:

• Find your target RPE in the left column
• Find your target reps in the top row
• The intersection shows what weight to use

The chart automatically rounds weights to your selected increment (2.5 lbs/kg by default) for practical loading.