One-Rep Max Calculator (Epley)
Estimate one-rep max with the Epley formula: 1RM ≈ w×(1+reps/30). Sample: 100 for 5 reps → ≈116.67. Educational estimate with a safety note — not coaching advice.
How it works
Enter a submaximal weight and successful reps. Treat the result as a classroom estimate, not a prescription.
Formula
1RM ≈ w(1+r/30). Notes:
- Accuracy falls as reps get high.
- Stop if form breaks — safety first.
- Pair with pace / body-fat educational tools.
Example
Example: w=100, reps=5 → 100×(1+5/30)=116.67.
When to use it
- Classroom strength math.
- Rough program sketch.
- Compare related fitness tools.
Frequently asked questions
Sample?
100×5 → ≈116.67.
Safe to test 1RM?
Not advice — use care and coaching.
Other formulas?
This page uses Epley only.
Advice?
Educational only.
Related tools
Questions or feedback
Something unclear, broken, or missing? Draft a message below — we read every note about these tools.