Calculate Your 1RM
Most accurate for 1-10 reps
Used to estimate calories burned during your deadlift set
Different formulas may give slightly different results. Epley is most commonly used.
Your Results
All Formula Results
Training Percentages
These percentages are commonly used for strength training programs
Estimated Calorie Burn
Based on your body weight and the weight lifted. This is an estimate for the deadlift exercise only. More advanced calculator →
Enter your lift data
Your results will appear here
Multiple Formulas
Choose from 7 scientifically-validated 1RM formulas or see the average of all for the most accurate estimate.
Training Percentages
Get precise training weights for any percentage of your 1RM to optimize your strength programming.
Unit Flexibility
Calculate in pounds (lbs) or kilograms (kg) - perfect for lifters anywhere in the world.
What is a One Rep Max (1RM)?
Your one-rep max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise. For deadlifts, it's the heaviest weight you can pull from the floor to lockout position with proper form.
Why Calculate Your 1RM? Knowing your 1RM is essential for:
- Programming effective strength training workouts
- Tracking progress over time
- Setting appropriate training loads (e.g., "5 sets of 5 at 80% 1RM")
- Competing in powerlifting or strength sports
How Does the Calculator Work?
This calculator uses established mathematical formulas to estimate your 1RM based on a weight you can lift for multiple reps. The most popular formula is the Epley formula:
We offer 7 different formulas because no single formula is perfect for everyone. Factors like training experience, muscle fiber type, and lifting technique can affect accuracy. Using the average of all formulas often provides the most reliable estimate.
Tips for Accurate Results
- Use proper form: Only count reps performed with good technique
- Stay in the 1-10 rep range: Formulas are most accurate with fewer reps
- Be honest about difficulty: Only count reps you could complete without assistance
- Test when fresh: For best accuracy, use weights lifted at the start of your workout
- Consider experience: Beginners may want to use conservative estimates
Different Rep Ranges
Different rep ranges serve different training goals. We have specialized calculators for popular rep ranges:
3 Rep Max
Strength training, Starting Strength
5 Rep Max
General strength, 5/3/1 program
10 Rep Max
Muscular endurance
Safety Note: Attempting a true 1RM can be risky and should only be done with proper preparation, spotters, and safety equipment. Using a calculator to estimate your 1RM is safer than testing it directly.