What is Black Box Testing? Everything You Need to Know

Without testing, you can’t be sure whether the software will perform impeccably or not. A group of people tests an app and web during and after the development. They are called testers. Testing is generally of three types: Black box testing, grey box testing, and white box testing. In this blog, professional testers will explain what is black box testing in a lucid way.

In our app development company, we have an experienced software testing team. It has handled various projects and found even tiny-tiny mistakes in software to save it from bad performance. So, you will get to know about black box testing and the crucial points related to it in this post.

If you know what is white box testing, it will be easy for you to understand what is black box test. So, I will begin by explaining white box testing. Scroll down to know everything.

What Is White Box Testing?

The internal structure of the software is checked that includes designs, functions, coding, structure, and others, it happens in white box testing. Open box, clear box, and transparent box testing are the other names of white box testing. According to the input values, the output values are measured.

Unit testing is the way of testing in all types of testing. It makes finding mistakes an easy task because a big task is divided into units.

What Is Black Box Testing?



Black box testing is like giving input values to a black box and getting output without knowing what happened inside the box. That is why it is also called the opaque software testing method, functional testing, closed-box testing, and behavioral testing method.

You can understand it with an example. When you write a topic on a search engine, after pressing enter you get some search results. You get the results without having an idea of internal structure, functions, and implementation details. You just get the output without carrying how it comes. Developers and designers also build MVP (Minimum Viable Product) to avoid mistakes. Black box testing is used widely for end-to-end user perspectives.



Software Development Life Cycle & Software Testing

Mentioning about software development life cycle becomes crucial if the post is about software testing. It is because testing can not be studied separately from SDLC as it is part of it.
Have a quick look at the SDLC 5 stages.

  1. Requirement Analysis
  2. Planning
  3. Design
  4. Implementation
  5. Testing

Also Read: What Are MVP Development Features?

Types of Black Box Testing

You can find many types of black box testing on the internet. I will cover the most important ones. It will help you understand the black box testing techniques effectively. So let’s begin.

  1. Functional Testing
  2. Non Functional Testing
  3. Regression Testing

1. Functional Testing

When a particular function of software requires testing, then functional requirements are analyzed and this type of testing is used. The tester checks the output of the given input. For example, when you enter the right password you can enter the phone, but the wrong password shows failed attempt.

Here are some crucial examples of black box testing.

  • Unit testing
  • User acceptance
  • Sanity testing
  • Integration testing
  • Smoke testing

2. Non Functional Testing

As the name implies, this black box test doesn’t concern with functional requirements. Various tasks come under non-functional testing. It checks how properly a system is working and the tasks in this type of testing are also designed accordingly. It checks the correct output.

  • Security testing
  • Performance testing
  • Compatibility testing
  • Usability testing

You can find out the below-mentioned things in this software testing life cycle.

  • The software is compatible to work with other devices
  • It can work in the maximum load
  • Easy to use

3. Regression Testing

Regression testing is helpful for checking changes in the code. It is especially when changes are done to the app’s design, features, and functions. Often due to new codes existing code gets disturbed and changes. So, with the help of regression black box tests, you can test new code that doesn’t affect the old or existing codes.

It is crucial to keep the actual output and high performance intact. Testers take the help of error guessing as well because it helps to find errors fast and save time.

How to Do Black Box Testing?

The development team has to follow some steps in order to do black box testing.

  1. First of all, an application is tested generally to find the requirements for testing. After this analysis, an SRS (Software Requirement Specification) is prepared to keep a record of every change.
  2. Examine and understand the software application, design parameters, and internal workings, and gain specific knowledge about the testing.
  3. Find whether changes in the specific feature are required or if you have to test for all the specifications and common mistakes.
  4. Create test cases so that input ranges can be maximum and help in testing.
  5. You can compare the actual output with the expected output by using some test cases.
  6. If there is any issue or unsuccessful steps, then the software development team fixes them.
  7. As the developers fix defects, testers test them again and inform about the problems.
  8. Testers keep on testing the app, web, or any software until all the problems are fixed.

When you want custom application development, many professionals work to complete your app impeccably. Testing is not post-development work, it takes place throughout the development.


Black Box Testing Techniques

There are mainly 5 types of black box testing techniques. Have a look.

  1. Equivalence Class Partitioning
  2. Boundary Values
  3. Decision Table
  4. State Transition
  5. Error Guessing

1. Equivalence Partitioning

Equivalence partitioning is used to reduce the number of test cases. It helps to maintain reasonable test coverage. The inputs are Boolean conditions or numeric values. For example, valid specifications are 1 to 20 inclusive. Invalid specifications would be less than 1 or more than 20.

2. Boundary Values

This type of technique is used for software testing when there is a specific type of boundary. When you design test cases, you have to decide on the inner and outer limits. For example, a website checks the age of candidates (Should be between 15-25) for a particular sports form. So, it will check the boundary for less than 15 and more than 25-year-old candidates.

3. Decision Table

Some conditions are set before the testing. So, if results come as per the set criteria then it comes under decision table testing. Let’s take an example, a government of a country provides various types of schemes and benefits. But they are different as per the requirement of the people and set criteria for people.

4. State Transition

Transitioning from one state to another is called state transition. This technique helps to develop a secure and smooth system. For example, when you try to unlock an app, due to many failed attempts it redirects you to any other page or message. So, it is called a transition from one state to another.

5. Error Guessing

As the name indicates, this technique is about guessing errors that can stay in the app. The tester has to be proactive to understand, which part of the app can contain errors in the future. If errors occur, how can they deal with them without affecting the existing coding, they need to guess everything.

Negatives and Positives of Black Box Testing


  • Designers and testers work separately so causes no conflict
  • Effective tests can be created
  • No technical knowledge is needed for testers
  • Black box helps in the easy implementation of apps


  • Sometimes no results come at the end
  • The complete software is not tested because more time is needed
  • Black box testing can’t be used for complex software
  • More number of test inputs, more time exhausting the task
  • The test can be redundant if a designer or developer has done it already

Final Words

Since testing is a crucial part of SDLC, professionals and a specific team is required that only focus on testing. It helps to produce error-free software that has high performance. Various techniques and tools are used for testing because finding all the errors manually are not possible for humans. Technource has a skilled team of skilled developers that have handled various complex projects to date. You can hire custom software developers at any time within your budget.



Mr. Sanjay Singh Rajpurohit, An early-aged entrepreneur who always leads his team from the front and achieved success. As the founder & CEO of Technource, a top mobile app & Web development company, he made a global presence in a short time by offering custom software development, premium mobile apps, and website development services to global clients. In his free time, he loves writing. He is featured on Hackernoon, Dzone, Enlear Academy, Articlesfactory, and much more websites.

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