function calculatePassRate() {
// Get input values using var
var totalInput = document.getElementById('pr_total_attempts');
var passInput = document.getElementById('pr_pass_count');
var resultContainer = document.getElementById('pr_result_container');
var mainPercent = document.getElementById('pr_main_percent');
var detailText = document.getElementById('pr_detail_text');
var barFill = document.getElementById('pr_bar_fill');
var errorMsg = document.getElementById('pr_error_msg');
// Parse values
var total = parseFloat(totalInput.value);
var passed = parseFloat(passInput.value);
// Reset display
errorMsg.innerHTML = "";
resultContainer.style.display = "none";
// Validation Logic
if (isNaN(total) || isNaN(passed)) {
errorMsg.innerHTML = "Please enter valid numbers for both fields.";
return;
}
if (total <= 0) {
errorMsg.innerHTML = "Total attempts must be greater than zero.";
return;
}
if (passed total) {
errorMsg.innerHTML = "Number of passes cannot exceed the total number of attempts.";
return;
}
// Calculation
var passRate = (passed / total) * 100;
var failRate = 100 – passRate;
// Formatting results to 2 decimal places if needed
var formattedPassRate = (passRate % 1 === 0) ? passRate.toFixed(0) : passRate.toFixed(2);
var formattedFailRate = (failRate % 1 === 0) ? failRate.toFixed(0) : failRate.toFixed(2);
// Update UI
resultContainer.style.display = "block";
mainPercent.innerHTML = formattedPassRate + "% Pass Rate";
detailText.innerHTML = "" + passed + " passed and " + (total – passed) + " failed out of " + total + " total.Failure Rate: " + formattedFailRate + "%";
// Update Visual Bar
barFill.style.width = passRate + "%";
// Change color based on score (Optional visual cue)
if(passRate < 50) {
barFill.style.backgroundColor = "#dc3545"; // Red for low
mainPercent.style.color = "#dc3545";
} else if (passRate < 75) {
barFill.style.backgroundColor = "#ffc107"; // Yellow/Orange for medium
mainPercent.style.color = "#d39e00";
} else {
barFill.style.backgroundColor = "#28a745"; // Green for high
mainPercent.style.color = "#28a745";
}
}
How to Calculate Pass Rate
Calculating the pass rate is a fundamental metric used in education, corporate training, software testing, and quality control manufacturing. It determines the percentage of successes relative to the total number of attempts. Whether you are a teacher grading exams or a manager analyzing project success, understanding this percentage is key to evaluating performance.
The Pass Rate Formula
The calculation is straightforward. You divide the number of successful outcomes (passes) by the total number of attempts (the sum of passes and failures), and then multiply by 100 to get a percentage.
Pass Rate % = (Number of Passes ÷ Total Number of Attempts) × 100
Conversely, if you need to find the failure rate, the formula is:
Fail Rate % = (Number of Fails ÷ Total Number of Attempts) × 100
Real-World Calculation Examples
Example 1: Classroom Exam
Imagine a class where 30 students sat for a final biology exam. After grading, the teacher finds that 24 students achieved a passing grade.
Step 1: Identify the Total (30) and the Passes (24).
Step 2: Divide Passes by Total: 24 ÷ 30 = 0.8.
Step 3: Multiply by 100: 0.8 × 100 = 80%.
Result: The pass rate for the biology exam is 80%.
Example 2: Quality Control (Manufacturing)
A factory produces 1,000 widgets in a single shift. During inspection, 50 widgets are rejected due to defects. This means 950 widgets passed inspection.
Step 1: Identify Total (1,000) and Passes (950).
Step 2: Calculate: (950 ÷ 1,000) = 0.95.
Step 3: Convert to percent: 0.95 × 100 = 95%.
Result: The production yield (pass rate) is 95%.
Why is Pass Rate Important?
Monitoring pass rates helps in identifying trends over time. In education, a sudden drop in pass rates might indicate that a specific curriculum is too difficult or wasn't taught effectively. In business, examining the pass rate of candidates in a recruitment funnel can help HR departments optimize their hiring process.