How do I use rep percentages?
For 5 reps at RPE 8-9, use ~85% of 1RM. For 10 reps, use ~75%. Adjust based on performance.
Health Fitness
Rep Max Calculator
Estimate rep max with quick inputs.
Fast, practical estimates
Adjust inputs for the most useful result.
What this calculator does
A rep max calculator estimates the weight you can lift for various rep ranges based on your 1RM or a known rep max. This helps program training using percentage-based or rep-based approaches.
How it works
Enter 1RM or a weight/rep combination. Calculator shows estimated weights for different rep targets.
Formula
% of 1RM by reps: 1 rep = 100%, 3 reps ≈ 93%, 5 reps ≈ 87%, 8 reps ≈ 80%, 10 reps ≈ 75%, 12 reps ≈ 70%.
Tips for using this calculator
- Use percentages for programming
- Strength work: 80-90% (3-6 reps)
- Hypertrophy: 65-80% (8-12 reps)
- Endurance: <65% (15+ reps)
- Individual rep-percentage relationship varies
Frequently asked questions
Are these percentages accurate for everyone?
General guidelines. Individual variation exists. Some are better at high reps, others at low reps.
Should I train at my rep max every set?
No, leave 1-3 reps in reserve most sets. Training to failure increases fatigue without proportional benefit.