Two views of your 1RM
The main result uses Epley. The smaller Brzycki estimate is a useful cross-check because the formulas respond differently as reps increase.
A tool for trainers and strength athletes
1RM and RPE Calculator
Enter the weight, reps, and optional RPE from a working set. You will get an estimated max and practical loads for your next sessions.
Your set
Enter your latest working set.
The estimate updates instantly. Turn RPE off to use weight and reps alone.
Weight unit
Use the actual load from your working set.
lb
Enter 1 to 12 technically sound reps.
RPE 10 means no reps left. RPE 8 is roughly two reps in reserve.
RPE reference chart
The chart shows the approximate percentage of 1RM for each combination of reps and RPE.
| Reps | RPE 10 | RPE 9.5 | RPE 9 | RPE 8.5 | RPE 8 | RPE 7.5 | RPE 7 | RPE 6.5 | RPE 6 |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 100% | 97.8% | 95.5% | 93.9% | 92.2% | 90.7% | 89.2% | 87.8% | 86.3% |
| 2 | 95.5% | 93.9% | 92.2% | 90.7% | 89.2% | 87.8% | 86.3% | 85% | 83.7% |
| 3 | 92.2% | 90.7% | 89.2% | 87.8% | 86.3% | 85% | 83.7% | 82.4% | 81.1% |
| 4 | 89.2% | 87.8% | 86.3% | 85% | 83.7% | 82.4% | 81.1% | 79.9% | 78.6% |
| 5 | 86.3% | 85% | 83.7% | 82.4% | 81.1% | 79.9% | 78.6% | 77.4% | 76.2% |
| 6 | 83.7% | 82.4% | 81.1% | 79.9% | 78.6% | 77.4% | 76.2% | 75.1% | 73.9% |
| 7 | 81.1% | 79.9% | 78.6% | 77.4% | 76.2% | 75.1% | 73.9% | 72.3% | 70.7% |
| 8 | 78.6% | 77.4% | 76.2% | 75.1% | 73.9% | 72.3% | 70.7% | 69.4% | 68% |
| 9 | 76.2% | 75.1% | 73.9% | 72.3% | 70.7% | 69.4% | 68% | 66.7% | 65.3% |
| 10 | 73.9% | 72.3% | 70.7% | 69.4% | 68% | 66.7% | 65.3% | 64% | 62.6% |
A formula helps with planning. It does not replace performance.
The Epley and Brzycki formulas estimate a maximum from one working set. They work best at low to moderate rep counts.
Know the limits
The formulas diverge more on longer sets. Use the result to guide training, not as a replacement for a safe max test.
Why plan with RPE
RPE lets the load follow performance on the day. A coach sets the rep range and effort, while the client chooses a load that fits.
Plan from performance, not guesswork.
Socra.fit brings the plan, RPE, logged sets, and client progress into one coaching system.
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