function calculatePassRate() {
// Get DOM elements
var totalInput = document.getElementById('totalCandidates');
var passedInput = document.getElementById('passedCandidates');
var errorMsg = document.getElementById('inputError');
var resultArea = document.getElementById('result-area');
// Get values
var total = parseFloat(totalInput.value);
var passed = parseFloat(passedInput.value);
// Validation logic
if (isNaN(total) || total <= 0) {
alert("Please enter a valid total number of candidates (greater than 0).");
return;
}
if (isNaN(passed) || passed total) {
errorMsg.style.display = 'block';
resultArea.style.display = 'none';
return;
} else {
errorMsg.style.display = 'none';
}
// Calculation Logic
var passRate = (passed / total) * 100;
var failRate = 100 – passRate;
// Formatting results to 2 decimal places
var passRateFormatted = passRate.toFixed(2);
var failRateFormatted = failRate.toFixed(2);
// Update DOM
document.getElementById('displayPassRate').innerHTML = passRateFormatted + "%";
document.getElementById('displayFailRate').innerHTML = failRateFormatted + "%";
document.getElementById('displayTotal').innerHTML = total;
// Update Visual Bar width
document.getElementById('passBar').style.width = passRateFormatted + "%";
// Show Results
resultArea.style.display = 'block';
}
How to Calculate Test Pass Rate
Whether you are a teacher analyzing classroom performance, an HR manager reviewing certification exam results, or a QA engineer tracking software test suites, calculating the Test Pass Rate is a fundamental metric for assessing success. It quantifies the proportion of attempts that met the required standard against the total number of attempts.
The Pass Rate Formula
The calculation for a pass rate is straightforward. It involves dividing the number of successful outcomes (passes) by the total number of attempts, and then multiplying by 100 to get a percentage.
Pass Rate (%) = (Number of Passes ÷ Total Number of Attempts) × 100
Conversely, to find the Fail Rate, you can simply subtract the Pass Rate from 100, or use the formula: (Number of Failures ÷ Total Attempts) × 100.
Step-by-Step Calculation Example
Let's look at a realistic example to illustrate the process:
Scenario: A professional certification board administers an exam to 150 candidates.
Outcome: After grading, it is determined that 120 candidates achieved a passing score.
Multiply by 100 to get the percentage: 0.80 × 100 = 80%.
Result: The pass rate for this exam session is 80%.
Why Monitoring Pass Rates is Important
Tracking this metric provides critical insights into different areas:
Educational Assessment: A very low pass rate might indicate that the curriculum was not taught effectively or that the test was too difficult. A 100% pass rate might suggest the test was too easy.
Software Quality Assurance: In automated testing, the pass rate indicates the stability of the software build. A drop in pass rate usually signals a regression or new bug.
Business KPIs: For training programs, pass rates measure the effectiveness of the training material and the ROI of the educational investment.
Common Factors Influencing Pass Rates
If you find your calculated rate is lower than expected, consider these variables:
Difficulty Level: Is the threshold for passing (the cut score) set too high?
Preparation: Did the candidates have access to adequate study materials?
Sample Size: With a small number of test takers (e.g., less than 10), a single failure can drastically skew the percentage.