1RM CALC

Whether you're serious about strength training or just starting your fitness journey, understanding your 1RM (One Repetition Maximum) is a game-changer. This powerful metric helps you gauge your current strength, tailor your workouts for optimal progress, and safely push your limits.

Weight Lifted Reps Performed Unit Formula

Most accurate for 2-10 reps.

Available Formulas

Epley One of the most popular; slightly higher estimates for lower reps than Brzycki.

Brzycki Commonly used; accurate for up to ~10 reps.

Adams General use.

Baechle Similar to Epley.

Berger Exponential model.

Brown Linear approximation.

Kemmler et al. Polynomial for better fit across ranges.

Landers Similar to Brzycki; sometimes called Lander.

Lombardi Power-based; simpler for calculations.

Mayhew et al. Designed for bench press but widely applied.

Naclerio et al. Exponential decay model.

O'Conner et al. Linear and straightforward.

Wathen Often used in sports training.

What is a 1 Rep Max (1RM)?

Your 1 Rep Max (1RM) is the absolute maximum amount of weight you can lift for a single repetition of a specific exercise with proper form. It's a fundamental measure of your maximal strength for that particular lift, such as a bench press 1RM, squat 1RM, or deadlift 1RM. Knowing your 1RM is crucial in strength training as it serves as a benchmark to track progress and structure your training programs effectively.

Why Use a 1 Rep Max Calculator?

Instead of risking injury or excessive fatigue by frequently attempting a true one-rep max lift, our calculator provides a reliable estimate based on your performance with submaximal weights.

Measure Strength Progress: Your 1RM is the gold standard for tracking strength gains over time.
Set Training Weights: Most effective programs are based on percentages of your 1RM.
Progressive Overload: As your estimated 1RM increases, adjust your training loads upwards.
Avoid Injury: Estimate your max without the physical strain of actually testing it.
Set Realistic Goals: Understanding your current strength helps you set achievable targets.

How to Use This Calculator

Enter Weight Lifted: Input the amount of weight you successfully lifted with good form.
Enter Repetitions: Input the number of reps completed. For best accuracy, use 2-10 reps.
Select Unit: Choose pounds (lbs) or kilograms (kg).
Click Calculate: Get your estimated 1RM instantly.

Understanding Your Results

Your calculated 1RM is an approximation of the heaviest weight you could lift for a single, perfect repetition. For example, if you bench pressed 200 lbs for 5 reps and the calculator shows 225 lbs, you could theoretically lift 225 lbs for one rep.

Use this to structure your workouts. If your program calls for 5 sets of 5 reps at 80% of your 1RM and your estimated 1RM is 300 lbs, you should use 240 lbs.

Tips for Accuracy & Safety

Good Form: Only count reps performed with proper technique.
Optimal Rep Range: Use a weight you can lift for 2-10 reps for best results.
Warm Up: Always perform a comprehensive warm-up before lifting heavy.
Use a Spotter: When performing sets close to failure on exercises like bench press or squats.
Listen to Your Body: Don't push through pain.

FAQ

How accurate is this calculator?

The Epley formula is generally quite accurate, especially when reps are between 2 and 10. However, individual factors like exercise type and form can influence your true one rep max.

How often should I calculate my 1RM?

Every 4-8 weeks is a good timeframe to reassess and update your training weights based on your new estimated 1RM.

Can I use this for any exercise?

Yes, you can use this calculator for any compound or isolation exercise. However, it's most commonly applied to major lifts like squat, bench press, and deadlift.

Health Disclaimer

This calculator is for informational purposes only. Always consult with a healthcare professional before starting any new exercise program. We are not responsible for any injuries that may result from your workouts.