Severity & Priority in Testing – What’s the Difference?

The severity of the Bug

The severity of the bug or the defect A problem or a Defect's severity in testing refers to how much of an impact it has on the software program under test. A higher severity rating indicates that the bug/defect has a greater impact on system functionality. The severity level of a bug or defect is generally determined by a Quality Assurance engineer.

What is the meaning of priority?

The order in which a fault should be repaired is referred to as a priority. The higher the priority, the faster the problem should be fixed.

Flaws that render the software system unworkable are prioritized above defects that affect only a tiny portion of the software's functioning.

Severity Vs Priority - The Main Difference

  • Priority refers to the order in which a developer should address a fault, whereas severity refers to the degree of influence a defect has on the product's operation.

  • Priority is divided into three categories: low, medium, and high, while severity is divided into five categories: critical, moderate, and severe. There are four types of cosmetic procedures: major, moderate, minor, and cosmetic.

  • Priority has to do with scheduling, whereas severity has to do with functioning or standards.

  • Priority refers to how quickly the fault should be rectified, whereas Severity refers to how important the flaw is to the product's functionality.

  • The manager/client decides on the priority of problems, whereas the QA engineer determines the severity levels of the faults.

  • Priority is determined by the worth of the business, whereas severity is determined by the functioning.

  • The priority value is subjective and liable to vary over time as the project circumstance changes, whereas the severity value is objective and less likely to alter.

  • Defects with a High Priority and Low Severity status must be corrected immediately but do not harm the application, whereas defects with a High Severity and Low Priority status must be fixed but not immediately.

  • Priority status is determined by client needs, whereas severity is determined by the product's technical aspects.

Severity Levels

Types of Severity of Bug/Defect may be divided into four categories in software testing −

  • This flaw implies that the process has been completely shut off, and no further action can be taken.

  • Major − This is a significant flaw that causes the system to fail. Certain elements of the system, however, are still operational.

  • Medium − It results in some unfavorable behavior, but the system remains functioning.

  • Low − It won't create any serious system failures.

Types of Priorities

Priority of bug/defect types may be divided into three categories −

  • Low − The flaw is an annoyance, but it can be repaired once the more important flaw has been addressed.

  • Medium − A flaw should be corrected throughout the usual course of development operations. It will have to wait till a new version is released.

  • High − The problem must be corrected as soon as feasible since it has a significant impact on the system and cannot be utilized until it is fixed.

How to Determine the Seriousness of a Defect?

  • Determine the frequency of occurrence − In some circumstances, the severity of a minor defect might be increased if it occurs frequently in the code. As a result, even if it is a tiny flaw, it is more serious from the user's perspective.

  • Isolate the flaw − Isolating the problem can assist in determining the impact's severity.

Difference between Priority and Severity

The sequence in which the developer should resolve defects is specified by Defect Priority.The defect severity of a fault is defined as the influence it has on the product's operation.
Priority is divided into three categories.

  • Low

  • Medium

  • High

There are five levels of severity.
  • Critical

  • Major

  • Moderate

  • Minor

  • Cosmetic

Priority has to do with scheduling.The term "severity" refers to the degree to which something is functional or adheres to a set of standards.
The priority of a bug determines how quickly it should be repaired.The severity of a problem on a product's functionality is indicated by its severity.
In consultation with the manager/client, the priority of faults is determined.The defect's severity level is determined by the QA engineer.
The business value determines priority.The severity of a situation is determined by its functioning.
Its worth is subjective and might fluctuate over time based on the project's circumstances.Its worth is objective and unlikely to fluctuate.
When a problem has a high priority and low severity, it means it has to be corrected right away but isn't affecting the application.When a fault has a high severity and a low priority, it means it has to be corrected, but not right now.
The priority status is determined by the needs of the consumer.The product's technical aspect determines the severity level.
During UAT, the development team prioritizes faults and fixes them.During SIT, the development team will prioritize and resolve bugs based on their severity.

Defect Severity and Priority Examples

Consider the following scenarios: low severity and high priority, and vice versa.

  • A logo problem for any shipping website can be of moderate severity since it will not hinder the website's performance, but it can also be of high importance because you don't want any subsequent shipments to proceed with the incorrect logo.

  • A flaw in reservation functionality that is of high severity but of low priority: Similarly, a defect in reservation functionality that is of high severity but of a low priority since it is expected to be released in the following cycle.

Triage of Defects

Defect triage is a technique that attempts to rebalance the process when the test team is faced with a challenge of limited resources. When there are a significant number of defects and a limited number of testers available to check them, defect triage assists in attempting to resolve as many problems as possible based on defect attributes such as severity and priority.

Defect Triage: How to Determine

Priority is typically used as the primary criterion for evaluating a problem in most systems. A good triage method, on the other hand, examines the severity as well.

The steps in the triage procedure are as follows −

  • The team reviews all flaws, even those that were rejected.

  • The substance of the problem, as well as its priority and severity settings, are used to make an initial assessment.

  • Determining the defect's priority based on the inputs

  • The product manager assigns the defect to the right release.

  • The problem is sent to the appropriate owner/team for further action.

Before choosing a severity level, every tester should examine the following guidelines

The tester evaluates the severity parameter, whereas the product manager or the triage team evaluates the priority parameter. To minimize confusion with the development team, it is critical for a tester to pick the correct severity when prioritizing a fault.

  • Understand the importance and severity of the concepts of priority and severity.

  • Always designate a severity rating to a problem depending on its category, since this will influence its priority.

  • Recognize how a certain situation or Test Case will affect the end-user.

  • It's important to think about how long it'll take to correct the fault and how long it'll take to verify it, based on its complexity.

An example of a high-severity yet the low-priority situation

Some older browsers render a webpage with several faults. The logo will not load, the text will jumble, and the graphics will be overly pixelated. The severity of the problem is significant since it affects both product functionality and user experience. However, because the issue primarily affects outdated browsers, it won't affect a big number of people. As a result, bug priority is low.

High-severity and high-priority example

On Chrome, a website is evaluated and found to be fully functional. However, while using Firefox, the price page has significant issues. The text that details the rates and matching features contained in each plan, as well as the buy buttons for purchasing plans, have vanished. Anyone using Firefox in this scenario is unable to purchase the merchandise or even learn the details of the goods being sold.

The severity of the defect is high since vital functionality is plainly harmed. Bug priority is high because the malfunctioning functionality obstructs a critical point of the customer experience (actually purchasing the goods).

An example of a low-severity yet the high-priority situation

When examining the operation of a website on Chrome, it is discovered that several buttons are slightly out of place. They can still be readily clicked and accomplish what they were designed to do. As a result, functionality is unaffected, and the severity of the defect is minor. Bug priority is high, though, because out-of-place buttons don't provide for a pleasant visual representation, and poorly designed websites actively turn off consumers. The problem must be resolved as soon as feasible.

An example of a low-severity, low-priority situation

During the testing of the website, mistakes were discovered in parts of the content, and the font and color did not match the website's primary design. This is, without a doubt, a bug, but it is by no means a functional issue. As a result, the severity of the defect is minimal. Similarly, it does not require rapid attention, therefore bug priority is low.

The Function of Real-Time Devices

Without understanding the actual nature of the defect, it is currently impossible to assign bug priority and severity. It's also crucial to understand how often a bug occurs and how it impacts the product.

Running software across actual devices and browsers is the best approach to find all issues. When it comes to website testing, make sure it's covered by both human and automated testing. Selenium automation testing should be used in conjunction with manual testing to ensure that no defects are missed throughout the Quality Assurance process.


In software engineering, assigning the improper severity to a defect can slow down the STLC process and have a significant impact on the team's overall performance. As a result, the individual in charge of defect assignment must be exact and accurate.

Updated on: 01-Dec-2021

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