One Rep Max Calculator

Training Percentages

Formulas: Epley, Brzycki, Lander (average of 3). Use as a guide — actual 1RM may vary.

How It Works

Your one rep max (1RM) is the most weight you can lift for a single repetition. Instead of testing your max, this calculator estimates it from submaximal sets using three proven formulas:

• Epley: 1RM = weight × (1 + reps/30)
• Brzycki: 1RM = weight × reps / (36 − reps)
• Lander: 1RM = (100 × weight) / (101.3 − 2.67123 × reps)

The result shown is the average of all three, giving a well-rounded estimate.