This calculator helps you quantify your strength and performance for specific exercises by providing key metrics derived from your body weight, the weight you lifted, and the repetitions performed. Understanding these numbers can be crucial for tracking progress, setting realistic goals, and optimizing your training program.
Key Metrics Calculated:
Weight Lifted (kg): The absolute weight you lifted for the specified number of repetitions.
Repetitions (Reps): The total count of times you successfully completed the lift.
Total Volume (kg): This metric represents the total amount of work done during an exercise set. It's calculated as Weight Lifted (kg) × Repetitions. Higher total volume generally indicates greater overall work and can be a good indicator of progress.
Relative Strength (Weight/Bodyweight): This is a fundamental measure of how strong you are in relation to your own body size. It's calculated as Exercise Weight (kg) / Body Weight (kg). A higher ratio indicates greater relative strength, meaning you can lift more weight compared to your body's mass. This is particularly important for bodyweight exercises and overall athleticism.
Estimated 1 Rep Max (1RM): The 1 Rep Max is the maximum amount of weight you can lift for a single repetition of a specific exercise. Estimating it is vital for program design, allowing you to work at specific percentages of your maximum strength. This calculator uses the Brzycki formula, which is widely used and generally accurate for estimating 1RM:
1RM = Weight Lifted × (36 / (37 – Repetitions))
This formula is derived from empirical data and provides a good benchmark for your maximal strength. Please note that this is an estimation and actual 1RM testing may yield slightly different results. For optimal results, the formula is most accurate for repetitions between 5 and 12.
How to Use This Calculator:
Input your current body weight in kilograms.
Enter the weight of the barbell/dumbbells/machine you lifted for a specific exercise.
Record the number of repetitions you successfully completed with that weight.
Click "Calculate Performance" to view your Total Volume, Relative Strength, and Estimated 1 Rep Max.
Applications in Training:
Tracking Progress: Regularly input your numbers after training sessions to see how your strength metrics are improving over time.
Goal Setting: Use the 1RM estimation to set specific strength targets for yourself.
Program Design: Determine appropriate training loads by calculating percentages of your estimated 1RM. For example, if your estimated 1RM for bench press is 100kg, training at 80% would involve lifting 80kg for your working sets.
Comparing Performance: Understand how your strength compares to others of similar body weight, especially with the Relative Strength metric.
Remember that consistency, proper form, and adequate nutrition are key to achieving your fitness goals. This calculator is a tool to help you understand and quantify your efforts.
function calculatePerformance() {
var bodyWeightKg = parseFloat(document.getElementById("bodyWeightKg").value);
var exerciseWeightKg = parseFloat(document.getElementById("exerciseWeightKg").value);
var reps = parseInt(document.getElementById("reps").value);
var resultDiv = document.getElementById("result");
var performanceOutput = document.getElementById("performanceOutput");
if (isNaN(bodyWeightKg) || bodyWeightKg <= 0) {
performanceOutput.innerHTML = "Please enter a valid body weight (kg).";
return;
}
if (isNaN(exerciseWeightKg) || exerciseWeightKg <= 0) {
performanceOutput.innerHTML = "Please enter a valid exercise weight (kg).";
return;
}
if (isNaN(reps) || reps 12) {
performanceOutput.innerHTML = "1RM estimation is most accurate for 5-12 reps. Please re-enter reps.";
return;
}
// Calculations
var totalVolume = exerciseWeightKg * reps;
var relativeStrength = exerciseWeightKg / bodyWeightKg;
// Brzycki formula for 1RM
var estimated1RM = exerciseWeightKg * (36 / (37 – reps));
// Display Results
var outputHtml = "