Empowering athletes and fitness enthusiasts with precision strength analytics
FitMax was born out of a simple observation: too many lifters were training blind. They would walk into the gym day after day, lifting weights without truly understanding their strength potential or how to optimize their training loads.
We saw athletes attempting dangerous max lifts without proper preparation, beginners struggling to find the right starting weights, and experienced lifters plateauing because they couldn't accurately track their progress. The solution was clear—we needed to make advanced strength calculation accessible to everyone.
At FitMax, we believe that data-driven training is the future of fitness. Every rep you perform contains valuable information about your strength potential. By using scientifically validated formulas like the Brzycki equation, we help you unlock that information without the risk of testing your absolute max.
Our calculator isn't just a tool—it's your training partner. It helps you:
We use the proven Brzycki formula, trusted by strength coaches and sports scientists worldwide for its precision in predicting one rep max values.
Every calculation is grounded in peer-reviewed research and validated training methodologies used by professional athletes and coaches.
Whether you're a complete beginner or a competitive powerlifter, our tool adapts to your experience level and training needs.
Understanding your one rep max (1RM) is fundamental to effective strength training. It's not about ego lifting or showing off—it's about having a baseline metric that allows you to:
Program Effectively: Most professional training programs are based on percentages of your 1RM. Whether you're following Wendler's 5/3/1, Westside Barbell, or any linear periodization model, you need to know your max to calculate your working sets correctly.
Measure Progress Objectively: "Feeling stronger" is subjective. Knowing your 1RM increased from 225 lbs to 245 lbs over 12 weeks is concrete evidence of progress. This data helps you evaluate if your training program is working or if you need to make adjustments.
Compete Confidently: If you're a competitive powerlifter or planning to enter your first meet, knowing your estimated maxes helps you choose appropriate opening attempts and plan your attempt progression.
We implement the Brzycki formula, which has been extensively validated in scientific literature. The formula accounts for the inverse relationship between weight and repetitions—as the weight increases, the number of reps you can perform decreases in a predictable pattern.
This formula is particularly accurate for rep ranges between 1-10 reps, which represents the strength training zone. Beyond 10 reps, you're entering muscular endurance territory where the formula becomes less reliable—which is why we cap our calculator at 12 reps with a warning.
Our team consists of certified strength coaches, competitive powerlifters, and sports science enthusiasts who understand the importance of accurate training data. We've spent countless hours in the gym ourselves, and we built FitMax to solve the problems we faced in our own training.
We're constantly refining our tool based on user feedback and the latest research in strength and conditioning. Our goal is to remain the most accurate, user-friendly, and scientifically sound 1RM calculator available online.
Privacy: We respect your data. We don't store your personal information or training data. Every calculation is performed in your browser and remains completely private.
Accessibility: Our calculator is 100% free and always will be. We believe everyone deserves access to quality training tools regardless of their budget.
Continuous Improvement: We regularly update our platform based on new research and user feedback. If you have suggestions or encounter issues, we want to hear from you.
Education: Beyond just providing a calculator, we aim to educate users about proper strength training principles, injury prevention, and evidence-based programming strategies.
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