RPE CALCULATOR
Enter the last weight you lifted and your perceived exertion to estimate your reps weight.
Your Last Set
Weight lifted
Reps
RPE
Min. Weight Increment (Optional)
Your Results
0
Estimated weight for reps
at RPE
What Is the RPE Calculator and How Do You Use It?
Our RPE Calculator is a simple but powerful tool that helps lifters estimate their one-rep max (1RM), plan future training loads, and better understand how hard they’re working in the gym. And it's all based on the Rate of Perceived Exertion (RPE) scale.
The calculator uses the 1–10 RPE scale, including .5 values, to reflect more precise levels of effort. This mirrors real-world lifting, where a set might feel tougher than an RPE 7 but not quite an RPE 8. The .5 increments help fine-tune programming and give you more accurate feedback.
We also have a more robust guide that answers What is RPE? It covers the 1-10 scale, what RIR means, and the difference between this and the Borg scale.
How It Works
To use the calculator, enter:
- The weight you lifted
- The number of reps performed
- The RPE rating for that set
Based on that information, the calculator will estimate your theoretical 1-rep max: the most weight you could lift for a single rep at maximal effort (RPE 10). It will also suggest possible working weights for different RPEs and rep ranges. This can help guide your next training session or assist with planning a strength block.
Note that we also have a 1-rep max calculator. Both of these can be useful tools for your strength training.
Troubleshooting
Why am I seeing an “invalid input” or NaaN result?
These usually happen if you've entered a number higher than 10 in the “reps” box. The RPE calculator works best when you measure lifts from 1-10. Higher rep counts will lead to less accurate data.
Why It Matters
The calculator is especially helpful if:
- You don’t want to max out but still want to estimate your strength
- You’re using RPE-based training and want to hit the right intensity
- You’re tracking progress over time based on effort, not just weight
Let’s say you did 225 pounds for 5 reps at RPE 8. The calculator can estimate your 1RM around 270 pounds. You can then use that number to plan future sets, knowing that you’re staying within the right intensity for your goals.
If you’re training with intent, not just chasing numbers, the RPE calculator gives you a smarter way to measure and manage your performance. Use it to stay on track, avoid burnout, and get stronger over time by listening to your body and using the data it gives you.
