10 Key KPIs Driving Continuous Improvement in QA Teams

This article explores the most important QA metrics in software development that help address any issues with the software before it goes out into the market, as well as assess how customer requirements are being met throughout the development stages.

This article explores the most important QA metrics in software development that help address any issues with the software before it goes out into the market, as well as assess how customer requirements are being met throughout the development stages.

December 6, 2023
Tamas Cser

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This article explores the most important QA metrics in software development that help address any issues with the software before it goes out into the market, as well as assess how customer requirements are being met throughout the development stages.

Quality Assurance (QA) teams are the guardians of application quality. They make sure that functional requirements are met, and they are also tasked with delivering a seamless user experience.

Key Performance Indicators (KPIs) are at the heart of this process - they offer valuable insights into the effectiveness, efficiency, and overall performance of testing. 

This guide will explore the most notable KPIs that QA teams should monitor to achieve continuous improvement in the modern software development landscape.

How have Quality Assurance KPIs changed in recent times?

The rise of agile development and DevOps has brought about a paradigm shift in how quality assurance teams think about KPIs. Agile methodologies rely heavily on feedback loops to measure progress, which requires QA teams to track their performance closely and regularly.. 

Quality assurance KPIs have shifted from identifying defects to providing actionable insights. This is done by measuring a range of metrics to understand the efficiency and effectiveness of testing processes. QA teams use these metrics to identify areas that need improvement and suggest strategies for achieving these improvements. The data can be used to manage resources and ultimately drive better results more effectively. Further, tracking KPIs over time can indicate the success or failure of any implemented changes.

Modern DevOps practices have also set the stage for a more automated approach to quality assurance, where KPIs are regularly measured and monitored across various stages of the SDLC. These changes pave the way for an environment where QA teams can confidently measure their performance and make improvements with each iteration.

KPIs: The Compass for Continuous Improvement

Quality assurance, when done right, goes beyond just hunting for bugs. It's about establishing a systematic process that constantly evolves and gets better. Think of KPIs not just as numbers but as a compass that gives direction and depth to QA initiatives. They provide tangible insights into team performance, highlighting strengths and areas where improvements can be made.

But the real magic happens when KPIs are integrated into daily operations. They help cultivate a culture of continuous improvement, where data-driven decisions guide the pursuit of excellence. Setting clear benchmarks, analyzing trends, and tracking progress over time, help QA teams elevate their strategies and enhance the entire development ecosystem, not just fix software.

What are the types of QA KPIs?

QA KPIs can be classified into two broad categories: process metrics and product metrics. Process metrics track key performance indicators related to the quality assurance processes, such as cycle time, defects per tester hour, defect detection rate, test coverage, number of bugs found in production etc. Product metrics measure success from the customer’s perspective, such as customer satisfaction, app performance, uptime/availability etc.

QA teams need to track and monitor both process and product metrics to deliver a high-quality product that meets customer expectations. With the right KPIs in place, they are better equipped to focus on areas of improvement and continuously measure their performance for better results. 

Top 10 Critical KPIs: The Metrics That Matter

It's important to focus on the most impactful KPIs - those that provide actionable intelligence without overwhelming teams with excessive data. Here are the top 10 KPIs that are key to shaping a strong QA strategy:

1. Test Coverage

Test coverage is a metric that quantifies the extent of testing conducted by evaluating the proportion of system components tested out of the total available. A higher test coverage is generally associated with reduced risks. Let's consider an example to clarify this concept.

Imagine you are a business owner preparing to launch a new e-commerce website. To ensure the website works flawlessly, you need to test various components such as product search, user registration, payment processing, and order fulfillment. Test coverage measures the percentage of these components that are tested. 

For instance, if you have 100 components and you have performed testing on 80 of them, your test coverage would be 80%. This means that 80% of the system's components have been examined, reducing the chances of potential issues when the website goes live. The higher the test coverage, the more confidence you can have in the stability and reliability of your platform.

2. Test Automation Coverage

Test automation coverage is the amount of functionality tested by automated tests. It can be measured in terms of how many features or scenarios have been tested, what percentage of the application has been covered, and how much time was spent on testing. Automated testing helps to ensure a consistent level of quality across development cycles and provides an efficient way for testers to run multiple tests quickly. 

Test automation coverage can also be used to measure the effectiveness of manual testing efforts in comparison to automated tests. Test automation coverage can help identify areas of the system that may require additional manual testing due to lack of automated test coverage. It is important to remember that there are always some parts of the system that may not be able to be automated. Manual testing will likely remain a necessary component of the testing process in order to identify and address any issues that are not covered by automated tests. As such, it is important to track both manual and automated test coverage in order to ensure comprehensive product quality assurance.

Test automation coverage will also help measure the return on investment for test automation efforts, so businesses can ensure that resources are justified and value-generating.

3. Defect Density

Defect density is a measure that calculates the number of defects found per unit size of a software module. Defects can be any errors or issues in the code that impact the functionality or quality of the software. The lower the defect density, the better the quality of the code.

Monitoring defect density helps QA teams assess the quality of their codebase and make informed decisions to improve and maintain software reliability and performance. It can also help by giving them an idea of where to focus their efforts to reduce the number of defects.

4. Test Efficiency

Test efficiency is the measure of how efficient your testing efforts are in uncovering defects in the software. It is measured by comparing the number of test cases run to the number of defects found. The higher the efficiency, the more effective your tests are in identifying defects.

Test efficiency helps QA teams understand how well their tests are able to find bugs and provide feedback on the efficacy of their testing efforts. The test efficiency metric helps teams identify areas that need improvement and where in the application they can improve their test coverage. It also helps determine how quickly a team is able to resolve defects by providing an indication of the number of defects identified per size of software module.

5. Test Effectiveness

Test effectiveness is a metric that calculates the percentage of defects found during testing but not in earlier stages like development or requirements analysis. It helps pinpoint areas where additional measures are needed to improve defect identification. 

Some QA teams may know another version of this: Defect Detection Effectiveness (DDE) or Defect Detection Percentage, which measures the overall effectiveness of regression testing. This is calculated by comparing the number of defects found before and after release by customers. Incidents found after release are logged into a help desk system, while defects found during testing phases are identified prior to release. The higher the metric, the better. The goal is to have a test effectiveness percentage of 100%, meaning that all defects were found before going live. 

In order to ensure a high test effectiveness percentage, it is important to keep track of metrics like defect discovery rate and time-to-fix. 

6. Defect Discovery Rate

Also known as defect detection rate, defect discovery rate (DDR) is a metric that measures how quickly defects are found and resolved compared to the total number of features tested. The DDR can be used to determine the effectiveness of your testing process. 

Dividing the number of defects detected, both in testing and in production, by the total number of defects found, gives you the defect discovery rate. A high DDR indicates that you’re able to detect and fix defects quickly, while a low DDR suggests that your tests are not catching all bugs or they are taking too long to fix.

The DDR is closely related to another metric: the Defect Removal Efficiency (DRE). The DRE 

evaluates the effectiveness of the testing process in identifying and removing defects before software is released. The formula for calculating the DRE is:

DRE = (Number of defects found and resolved during testing/Total number of defects) * 100.

A higher DRE means that more defects were identified and fixed in the testing phase, which leads to a higher quality product being released. A lower DRE suggests either that the tests are not comprehensive enough, or that the process for defect fixing is inefficient.

It's important to monitor both the DDR and DRE. Making sure that these metrics are consistently high will ensure that you can deliver a quality product with minimal defects. 

7. Time Metrics - Mean Time to Detect (MTTD) and Mean Time to Repair (MTTR)

These two metrics measure the amount of time it takes for a company to detect and repair a product issue once it has been reported. MTTD is the average length of time from when an issue is first reported until it is detected by the company, while MTTR is the average length of time from when an issue is detected until it is fixed or resolved. Tracking these two metrics can help businesses identify areas where they may need to better their product or service by ensuring quicker response and repair times. 

8. Escaped Defects

As the name suggests, escaped defects are those that managed to slip through your testing process and end up in production. These defects are typically reported by customers after the software has been released. Escaped defects can be caused by changes made to the code without proper regression testing or simply not having a rigorous enough test suite.

This metric can indicate where or how you may need to consider implementing measures to ensure that any code changes are properly tested before they’re pushed out to production. Ensure that your test suite is running frequently enough so that any potential issues can be detected quickly and resolved as soon as possible.

A metric related to escaped defects is Defect Leakage, which refers to the defects that slip through the cracks and are discovered in the UAT stage. This means that if you are addressing defect leakage, you are trying to reduce the number of defects before they reach the customers. So, tracking this metric would be a way to drive down the escaped defects. This, in turn, would help increase customer satisfaction and give more confidence in the product. 

9. Customer Satisfaction Score (CSAT)

The Customer Satisfaction Score (CSAT) is a metric used to gauge customer satisfaction with a product or service. It involves collecting user feedback after product release to assess if it meets or exceeds expectations. Linking QA to user satisfaction through the CSAT metric helps businesses evaluate product/service effectiveness and pinpoint areas for improvement. This metric should be tracked over time to determine if improvements are being made and customer expectations are met. 

Tracking changes in the CSAT score helps businesses see how their products or services are doing with respect to customer satisfaction, and also helps them identify areas that may need improvement in order to better serve their customers.

10. Defects per Software Change

Defects per software change is an important metric used to measure the number of defects discovered in a certain period of time after a new version or feature release.This metric is particularly useful in today’s landscape, where software and applications are constantly undergoing updates and changes.Tracking the number of defects per change will help businesses get a better understanding of how effective their development process is and identify areas that need improvement. This metric can also help teams prioritize which issues should be addressed first in order to minimize disruption to customers when releasing new features or updating existing ones.

The defects per software change is related to another metric that correlates defects found with changes in the software: Defect Distribution over Time. This metric measures the number of defects found over a set period of time after a change has been made. It helps determine if the testing process is progressing effectively in uncovering problems before releasing new software or features. 


In the pursuit of software excellence in an era of ever-accelerating digital transformation, quality assurance is key to ensuring success. KPIs guide QA teams through rapid development cycles, complex requirements, and heightened user expectations. They provide a way for organizations to track their progress and optimize their efforts to ensure the best possible product or service reaches the end customer. Quality assurance not only enables organizations to avoid costly mistakes, but also to build trust and confidence in their brand as they deploy reliable technology solutions that meet the end user’s expectations.

But remember, the key to realizing the true value of these KPIs lies in understanding that these are not static, one-off metrics. They demand regular review and realignment with organizational goals, technological advancements, and market demands. 

Quality assurance is a fundamental part of any software development approach, and finding the right mix of QA techniques, tools, and metrics can be key to successful execution.