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1RM Calculator – Estimate Your One Rep Max
Calculate your one-repetition maximum using scientifically-validated Epley and Brzycki formulas. Get accurate strength estimates for precise training program design and progressive overload planning.
How to Use Your 1RM Result
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What is 1RM?
One Repetition Maximum (1RM) is the maximum weight you can lift for a single repetition with proper form. It's the gold standard for measuring absolute strength and serves as the foundation for designing effective training programs across all fitness goals.
How It's Calculated
Our 1RM calculator uses two scientifically-validated formulas: the Epley formula (robust across all rep ranges) and the Brzycki formula (most accurate for 1-10 reps). These formulas estimate your maximum strength from submaximal efforts, eliminating the need for dangerous true 1RM testing.
Why It Matters
Knowing your 1RM allows you to calculate precise training percentages for different goals. Whether you're building strength (80-90% of 1RM), muscle (70-80% of 1RM), or power (60-70% of 1RM), these percentages ensure optimal training stimulus and progressive overload.
For comprehensive training strategies and program design, check out our complete 1RM guide.
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