Calculate your maximum strength for any exercise using multiple scientific formulas. Perfect for powerlifters, bodybuilders, and gym beginners to plan effective training programs.
This is your estimated maximum weight for one repetition with proper form.
Use this table to determine training weights based on your 1RM percentage.
| Reps | % of 1RM | Weight (kg) | Weight (lb) |
|---|
💡 Pro Tip: Commonly used rep ranges for training are highlighted in green. Use 5 reps for strength, 8 for hypertrophy, and 10+ for endurance.
Input the weight you lifted in your last training session. Use kg or lb based on your preference.
Enter how many repetitions you performed with that weight (between 1 and 15 reps).
Select your preferred calculation method or use "Average" for the most balanced estimate.
Click calculate to see your estimated one rep max and training weights for different rep ranges.
Your one-rep max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise with proper form. It's a standard measurement used in strength training to gauge progress and plan workouts.
Knowing your 1RM helps you:
Actual 1RM testing carries injury risk for beginners. Instead, use this calculator to estimate your 1RM based on submaximal lifts (5-10 reps). This provides a safe alternative while allowing you to plan appropriate training intensities.
A good one rep max varies based on gender, body weight, training experience, and exercise. For beginners, lifting your body weight on compound lifts is a solid starting goal. Intermediate lifters often aim for 1.5x body weight, while advanced athletes may exceed 2x body weight.
1RM calculators provide estimates based on mathematical formulas, not actual testing. They're generally accurate within 5-10% for most people when using proper form. Actual 1RM testing is more accurate but carries higher injury risk.
The Epley formula is most commonly used and provides reliable estimates for 1-10 reps. Brzycki is often more accurate for lower rep ranges (1-5), while Lombardi works well for power-based movements. We recommend using the average of all formulas for the most balanced estimate.
Yes, beginners can use 1RM calculators safely to estimate training weights without attempting a true 1RM lift. This helps determine appropriate starting weights for different rep ranges while minimizing injury risk from max attempts.