One Rep Max (1RM) Calculator & Strength Program Builder
Free NSCA-based 1RM calculator with percentage-based program generator, training max manager, and workout logger.
One Rep Max (1RM)-Based Training Guide
| Goal | % of 1RM | Reps | Sets | Rest |
|---|---|---|---|---|
| Max Strength | 90-100% | 1-3 | 4-6 | 3-5 min |
| Strength | 80-90% | 3-6 | 3-5 | 2-4 min |
| Hypertrophy | 65-80% | 6-12 | 3-5 | 1-2 min |
| Endurance | 50-65% | 12-20+ | 2-3 | 30-90 sec |
Frequently Asked Questions
What is One Rep Max (1RM)?
Your One Rep Max (1RM) is the heaviest weight you can lift for a single repetition with proper form. It serves as the foundation for percentage-based training programs.
- Sets training intensity as a percentage of your max
- Tracks strength progress over time
- Helps periodize training programs
- Allows comparison across lifters and bodyweights
How We Calculate
Estimated One Rep Max (1RM) = Weight x Conversion Coefficient. We use NSCA lift-specific coefficients by default, which account for different fatigue curves across squat, bench, and deadlift. Epley, Brzycki, and Lombardi are also available as general-purpose alternatives.
Disclaimer: All results are estimates for reference only. Actual One Rep Max (1RM) varies with technique, fatigue, nutrition, and recovery. Beginners should avoid maximal singles and use sub-maximal sets to estimate. Always use proper form and a spotter for heavy lifts. Consult a qualified coach for individualized programming.