One-Rep Max Calculator
Your One-Rep Max Results:
Common training percentages based on your One-Rep Max:
What is a One-Rep Max Calculator?
A One-Rep Max (1RM) Calculator is a fitness tool that helps you estimate the maximum weight you can lift for a single repetition of an exercise based on the weight you can lift for multiple repetitions. This calculation is valuable for strength training program design, tracking progress, and setting realistic strength goals.
How Our One-Rep Max Calculator Works
Our calculator uses scientifically-validated formulas to estimate your 1RM without requiring you to actually perform a potentially dangerous maximum lift attempt. Simply input the weight you’ve successfully lifted, the number of repetitions completed, select your preferred formula, and the calculator will do the rest.
Multiple Formulas
Choose from different validated formulas including Brzycki, Epley, Lombardi, Mayhew, or use the recommended average for the most accurate estimation.
Training Percentages
Get instant calculations of common training percentages (60%-95%) based on your estimated 1RM for effective program design.
Unit Flexibility
Easily switch between kilograms (kg) and pounds (lb) to match your preferred weight measurement system.
Benefits of Knowing Your One-Rep Max
Understanding your 1RM provides numerous advantages for your strength training program:
- Personalized Programming: Design training programs with precise percentage-based loading schemes
- Progress Tracking: Objectively measure strength gains over time
- Goal Setting: Establish realistic and achievable strength targets
- Injury Prevention: Avoid attempting true 1RM lifts which carry higher injury risk
- Competition Preparation: For powerlifters and strength athletes, estimate competitive potential
When to Use Different Formulas
Each formula in our calculator has unique characteristics that may make it more suitable for certain scenarios:
- Brzycki: Generally more accurate for higher rep ranges (8-10)
- Epley: Considered accurate for moderate rep ranges (3-10)
- Lombardi: May be more accurate for experienced lifters
- Mayhew: Often preferred for upper body exercises
- Average: Our recommended option that balances all formulas for the most reliable estimate
Frequently Asked Questions
Start Optimizing Your Training Today
Whether you’re a beginner looking to establish baseline strength metrics or an experienced lifter fine-tuning your program, our One-Rep Max Calculator provides the insights you need to train smarter, not just harder. Use the calculator above to get started!