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Calculate your estimated one rep max (1RM) using four validated formulas. Includes rep-max table, strength standards relative to body weight, and formula comparison cards.
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Your one rep max (1RM) is the maximum weight you can lift for a single repetition with proper form. It is the gold standard for measuring strength and is used to set training loads for strength programs.
Training zones based on 1RM:
Safety note: Attempting a true 1RM requires a spotter and proper warm-up. Use estimated 1RMs from submaximal lifts for day-to-day training.
Most widely used, accurate for 1-10 reps.
Preferred for higher rep ranges (up to 15).
Better for explosive lifts like power cleans.
Accurate for 1-6 rep range.
The Epley formula is the most widely validated for the 1-10 rep range. Brzycki performs better for higher rep ranges (10-15). Taking the average across all four formulas gives the most reliable estimate for most lifters.
Most programs recommend testing every 4-12 weeks. Beginners should use estimated 1RMs from submaximal lifts rather than attempting true max lifts. Intermediate and advanced lifters can test more specifically for competition needs.
Strength relative to body weight is a better measure than absolute numbers. A 1.5x body weight bench press or 2x body weight squat is considered intermediate for men. The strength standard chart in the calculator shows where you rank by lift and gender.
Yes, but the formula accuracy varies by lift. The formulas work best for compound lifts (bench press, squat, deadlift) because they involve multiple muscle groups. Isolation exercises may not follow the same strength-curve pattern.
Training at your 1RM is not recommended for regular workouts due to high injury risk and CNS fatigue. Use percentages of your estimated 1RM (e.g., 70-85% for most training) and only attempt true 1RM lifts when properly prepared with a spotter.