🏋️ Maximal Strength & 1RM Load Estimator
One Rep Max (1RM) Calculator
Calculate your estimated One Rep Max using 7 exercise science formulas (Brzycki, Epley, Lander, Lombardi) with full percentage training load tables.
reps
Sample Lifts:
Bench: 225 lbs × 5
Squat: 315 lbs × 3
Deadlift: 405 lbs × 4
100 kg × 6 reps
Estimated One Rep Max (1RM Average)
255 lbs
Comparison Across 7 Established Biomechanical Formulas:
Brzycki
253.1
Epley
262.5
Lander
255.8
Lombardi
264.4
Strength & Hypertrophy Training Percentages Table:
| % of 1RM | Training Weight | Rep Range Capacity | Training Focus |
|---|
The Biomechanics of 1RM Formulas
Direct maximal 1RM testing carries elevated injury risk under fatigue. Exercise physiologists estimate 1RM safely using submaximal loads:
- Brzycki Formula: $1RM = w \times \frac{36}{37 - r}$ (Ideal for 1 to 10 reps)
- Epley Formula: $1RM = w \times (1 + 0.0333 \times r)$
- Lander Formula: $1RM = \frac{100 \times w}{101.3 - 2.67123 \times r}$