One Rep Max Calculator

What is One Rep Max (1RM)?

One Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form. It is considered the gold standard for measuring absolute strength in movements like Squats, Bench Presses, and Deadlifts.

Why Predict Instead of Testing?

Testing your true 1RM is physically demanding and carries a higher risk of injury to the central nervous system and joints. This calculator uses scientific formulas like Brzycki** and **Epley to safely estimate your max based on 3-10 repetitions, allowing you to track progress without the risk.

Training Percentages & Goals

Knowing your 1RM allows you to program your workouts with precision:

• Absolute Strength: 85-95% 1RM (1-5 reps per set)
• Hypertrophy (Muscle Growth): 65-80% 1RM (8-12 reps per set)
• Muscular Endurance: Below 60% 1RM (15+ reps per set)

Pro Tip: Progressive Overload

Strength progress isn't linear. We recommend re-estimating your 1RM every 4-8 weeks to adjust your training weights. This ensures you are consistently applying Progressive Overload, the key to long-term gains.