Fitness
One Rep Max Calculator
Calculate your one rep max and training percentages
How to Use the One-Rep Max Calculator
Estimate the maximum weight you can lift once from a lighter set.
- Enter the weight you lifted.
- Enter how many reps you completed.
- See your estimated 1RM and training percentages.
1RM Formula (Epley)
Epley
1RM = weight × (1 + reps / 30)
A widely used estimate from submaximal sets.
Example:
Input: 100 kg × 5 reps
Calculation: 100 × (1 + 5/30)
Result: ≈ 116.7 kg
Real-World Use Cases
Program Design
Set working weights as a % of 1RM.
Progress Tracking
Compare estimated maxes over time.
Tips
Tips
- Estimates are most accurate under ~10 reps.
- Don't attempt a true 1RM without warm-up and a spotter.
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