5 10 15 Rep Max Calculator Kg

The 5-10-15 rep max calculator helps you estimate your one-rep maximum (1RM) in kilograms using the Brzycki formula. This method is commonly used in strength training to determine your maximum lifting capacity for a specific exercise.

What is the 5-10-15 method?

The 5-10-15 method is a simple way to estimate your one-rep maximum (1RM) based on your performance in three different rep ranges. The method uses the Brzycki formula, which is one of the most accurate formulas for estimating 1RM.

The formula works by taking your weight lifted in three different rep ranges (5, 10, and 15 reps) and calculating an average 1RM estimate. This gives you a more accurate estimate than using just one rep range.

Key Points

More accurate than single-rep estimates
Uses three different rep ranges for better accuracy
Works for both strength training and powerlifting

How to use this calculator

To use the 5-10-15 rep max calculator:

Enter the weight you lifted for 5 reps in kilograms
Enter the weight you lifted for 10 reps in kilograms
Enter the weight you lifted for 15 reps in kilograms
Click "Calculate" to see your estimated 1RM

The calculator will display your estimated one-rep max in kilograms, along with a chart showing the relationship between reps and weight.

Formula used

The calculator uses the following formula to estimate your one-rep max:

1RM = (Weight × 36) / (37 - Reps)

Where:

Weight = the weight you lifted
Reps = the number of repetitions you performed

The calculator averages the estimates from the three rep ranges to provide a more accurate estimate of your one-rep max.

Worked example

Let's say you lifted:

100 kg for 5 reps
80 kg for 10 reps
60 kg for 15 reps

Using the formula:

For 5 reps: (100 × 36) / (37 - 5) = 100 × 36 / 32 = 112.5 kg
For 10 reps: (80 × 36) / (37 - 10) = 80 × 36 / 27 ≈ 103.7 kg
For 15 reps: (60 × 36) / (37 - 15) = 60 × 36 / 22 ≈ 96.36 kg

The average of these estimates is (112.5 + 103.7 + 96.36) / 3 ≈ 104.5 kg, which would be your estimated one-rep max.

FAQ

What is the 5-10-15 method?: The 5-10-15 method is a way to estimate your one-rep maximum (1RM) by using weights lifted at 5, 10, and 15 repetitions. It provides a more accurate estimate than using just one rep range.
Is this method accurate?: The Brzycki formula used in this method is one of the most accurate formulas for estimating 1RM. However, individual results may vary based on factors like fatigue, technique, and recovery.
Can I use this for any exercise?: Yes, the 5-10-15 method can be used for any strength training exercise, including squats, deadlifts, bench press, and overhead press.
How often should I use this method?: You can use this method whenever you want to estimate your 1RM. It's particularly useful when you're tracking your progress over time.