1-Rep-Max (1RM)
Enter the weight and reps of a clean set (no grind to failure if possible). We’ll estimate your 1RM, show common training %s, and suggest a simple warm-up ladder.
Estimated 1RM
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Suggested warm-up (barbell)
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| % of 1RM | Weight (kg) | Weight (lb) | Est reps* |
|---|
*Very rough reps-at-% guidance assuming non-grindy sets. Individual
response varies.
About formulas
Epley: 1RM = W × (1 + R/30). Works well 1–10 reps.
Brzycki: 1RM = W × 36/(37 − R). Often conservative at higher reps.
Use recent, well-executed sets. Very high reps (10+) tend to overestimate.
Help & FAQ — One-Rep Max Calculator
How to use
- Enter the weight lifted and the number of reps completed.
- Select which estimation formulas you want to compare.
- Review the predicted 1RM and suggested training percentages.
Use cases
- Estimate your 1RM from a working set.
- Calculate training percentages for strength blocks.
Tips & FAQs
- Which formula should I trust?
- Use multiple formulas to get a range; choose the one that aligns with your training history.
- Can I track progress?
- Use the share/save feature to keep snapshots over time; the tool stores nothing server-side.
Formats & limits
- Input reps: 1–12
- Supports metric and imperial units
- Estimates assume steady effort—actual strength varies day to day
Privacy
Calculations run locally in your browser; no data leaves your device.
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Updated
15 October 2025