The actual time spent on tasks completed so far (Hours/Days/Weeks).
How long you originally estimated the completed tasks would take.
The original estimate for the entire project timeline.
Rate of Performance (RP):0%
Project Status:–
Projected Total Duration:0
Estimated Variance:0
How to Calculate Rate of Performance in Project Management
Rate of Performance (RP) is a critical metric used in project management—specifically within the Critical Chain Project Management (CCPM) methodology—to forecast project completion dates based on current progress. Unlike simple status reports, RP provides a quantitative measure of the "pace" at which the project team is working relative to the original plan.
What is the Rate of Performance Formula?
The Rate of Performance is calculated by comparing the actual time elapsed against the planned time for the work that has been completed. The formula is:
RP = Actual Duration / Planned Duration for Work Completed
Using this ratio, a Project Manager can then forecast the Projected Total Duration of the project:
Projected Duration = Total Planned Project Duration × RP
Interpreting the Results
Understanding your RP value is essential for realistic scheduling:
RP = 1.0 (100%): The project is progressing exactly as planned.
RP > 1.0 (e.g., 125%): The project is progressing slower than planned. For every hour estimated, it is taking 1.25 hours. The project is likely to finish late.
RP < 1.0 (e.g., 80%): The project is progressing faster than planned. Work is being completed in less time than estimated.
Why Use This Calculator?
Traditional Critical Path Method (CPM) often focuses on "float" or "slack," but Critical Chain methods focus on buffers and rate of consumption. By calculating the Rate of Performance early in a project, you can identify trends before they become crises. If your RP is consistently 1.2 after the first few tasks, it is statistically probable that the remainder of the project will follow the same trend unless corrective action is taken.
Example Calculation
Imagine a software development project estimated to take 100 days in total.
You are currently in the coding phase.
The work completed so far was estimated to take 20 days.
However, it actually took 25 days to finish that specific work.
Step 1: Calculate RP
RP = 25 / 20 = 1.25 (or 125%)
Step 2: Forecast Total Duration
Projected Total = 100 days × 1.25 = 125 days
This indicates the project is trending 25 days late based on current performance.
function calculatePerformance() {
// 1. Get Input Values
var actualDuration = parseFloat(document.getElementById("actualDuration").value);
var plannedDuration = parseFloat(document.getElementById("plannedDuration").value);
var totalScope = parseFloat(document.getElementById("totalProjectScope").value);
// 2. Clear previous error styling or alerts (simple approach)
var resultArea = document.getElementById("result-area");
// 3. Validation Logic
if (isNaN(actualDuration) || isNaN(plannedDuration) || isNaN(totalScope)) {
alert("Please enter valid numbers for all fields.");
return;
}
if (plannedDuration <= 0) {
alert("Planned Duration for completed work must be greater than zero to calculate a rate.");
return;
}
if (actualDuration < 0 || totalScope 1.0) {
statusElement.innerText = "Behind Schedule (Slower than planned)";
statusElement.className = "result-value status-bad";
} else if (rpRatio 0) {
varianceElement.innerText = "+" + variance.toFixed(2) + " units (Late)";
varianceElement.style.color = "#e53e3e";
} else if (variance < 0) {
varianceElement.innerText = variance.toFixed(2) + " units (Early)";
varianceElement.style.color = "#38a169";
} else {
varianceElement.innerText = "0 units (On Time)";
varianceElement.style.color = "#2d3748";
}
}