Skip to main content
  • The Wellington City Council (WCC) wanted to deliver quality outcomes without breaking the bank. Find out how Planit’s fast and flexible resources helped WCC achieve this goal.

this is a test Who We Are Landing Page

INSIGHTS / Articles

The Six Thinking Hats of Exploratory Testing

 26 Mar 2018 
The Six Thinking Hats of Exploratory Testing The Six Thinking Hats of Exploratory Testing
The Six Thinking Hats of Exploratory Testing
INSIGHTS / Articles

The Six Thinking Hats of Exploratory Testing

 26 Mar 2018 

In this era of increased speed-to-market where focus is more on Lean and Agile, exploratory testing has become more significant than ever. Testers frequently face the challenge of delivering results without having enough time to plan and design their tests. This leads to incomplete test coverage and defect leakage into production.

It would be of great benefit to have a fool-proof mechanism to help design the tests covering all aspects of a product or a project, thereby ensuring greater test coverage. This is where the six thinking hats of exploratory testing come in.

Applying Edward de Bono’s six thinking hats principles to exploratory testing can work wonders and empower the testers by inspiring confidence in them with better test coverage.

What is exploratory testing?

Exploratory testing is a form of testing where one continuously refines their testing approach based on how the application under test responds.

It is arguably the most misinterpreted testing technique. More often than not, it is assumed to be a random or ad-hoc form of testing which lacks structure and planning; when in fact, exploratory testing should be performed as a well thought-out process. Although testers typically learn the product, design the test cases and execute them, all at the same time, there ought to be an organised approach while doing so.

The flexibility of exploratory testing should be leveraged towards improving the overall product quality without falling for the chaos that unplanned, immature tests may bring. If planned well, exploratory testing can yield great results. Some benefits of this approach include continuous improvement of tests, uncovering of the not-so-obvious defects, and learning on the go. However, it is easy to go astray without direction and alignment of thoughts.

Session-based testing

There are various ways in which exploratory testing can be structured to achieve its intended results, session-based testing being the most popular practice. Session-based testing has been established on the fact that the human brain can only concentrate on one topic for a limited amount of time.

Splitting up the testing window into smaller sessions increases productivity and yields better results. One of the ideas that can further enhance these sessions of exploratory testing is applying Edward de Bono’s famous lateral thinking technique known as “Six Thinking Hats”.

Edward de Bono’s thinking hats

The Six Thinking Hats is a lateral thinking tool designed to provide structure to the thinking of an individual or a group. It was devised by Edward de Bono, who has always been an advocate of learning and adopting “thinking methods” to aid with decision making.

Six Thinking Hats is a parallel thinking technique which steers one’s thought process in a detailed and cohesive manner. The six hats represent six different focus areas of a problem or the subject in discussion.

Switching the hats one by one ensures that all aspects of the subject have been considered and analysed. By bearing in mind all alternatives, the probability of getting restricted to one perspective can be greatly reduced, if not eliminated.

The thinking hats principles can benefit the teams while making group decisions or even while working in silo. In the case of teams, it helps to have a co-ordinator to make sure that everybody in the team is wearing the same hat at any given point.

The Blue Hat

Blue hat is used to manage the thinking process. It represents the big picture, the overview. With the blue hat on, one can, for example, plan how much time should be spent on the other hats. Once all the other hats have been considered, one can take up the blue hat again for final decision making.

The White Hat

White hat represents facts and information. With the white hat on, one should focus on all possible information known about the subject in question. No assumptions, just facts.

While this helps one understand, what is known about the subject, it also directs towards the unknown. With the right questions asked, useful information can come to light.

The Red Hat

Red hat represents emotions and feelings. One is allowed to echo their feelings without being judged or without having to give an explanation. The statements that result from putting the red hat on could be as strong as “I hate this UI” or “I think the stakeholders will love this!”

The Yellow Hat

Yellow hat denotes positivity and optimism. Focus is on the benefits and advantages of a particular approach or solution; just the bright side with no consideration of pit falls.

The Black Hat

The black hat is the “critique” with emphasis only on the negatives and finding out the reasons why an approach or a solution will not work. Failure to work could be due to cost, feasibility or associated risks. The idea is to expose all the loop holes that prevent the solution from achieving the desired result.

The Green Hat

The green hat signifies creativity and innovation, an out-of-the-box solution to a problem. By putting on the green hat, one can concentrate on ideas and solutions that may not have been considered with all the other hats. Green hat contributes towards uncovering unconventional approaches to problem solving.

The below table presents the essence of each of the six hats:

Six Thinking Hats

Applying the six thinking hats to exploratory testing

It becomes increasingly difficult to plan under pressure. Even the most avid “planners” may miss a few details and alternatives while outlining a test plan or a strategy. To have a ready-to-use template to think decisively by categorising the tests into most significant areas or aspects can only help create a comprehensive plan, without having to spend much time thinking about what those aspects are. 

Combining Edward de Bono’s six thinking hats principles to exploratory testing can yield powerful results. When given an application to test, the testers can divide their time in such a way that they get enough time with each of the hats.

It is important to not overlap the hats during this process. For example, while wearing a yellow hat, one should not think of negative test cases, and should only focus on the positive, happy path scenarios. This will help to keep the mind focused on all directions one-by-one, ensuring better coverage and avoiding chaos resulting from over-crowding of thoughts.

Planning the test session would be a blue hat activity. How much time should be spent on each of the other hats or whether the plan is being adhered to are some of the questions that are answered by the blue hat.

Six Thinking Hats

A practical example

Following a session-based testing approach, let us look at the example of testing a login page. The assumption here is that the test session is two hours long.

Applying the six thinking hats principles, the first hat that we would put on is the blue hat, where we plan for the two hours of testing. For example, we can spend 15 minutes with blue hat, 25 minutes with white hat and 20 minutes each with the rest of the hats.

As we proceed with testing, revising the plan may become necessary. So, at any given point, irrespective of what hat is on, we can always go back to the blue hat.

The table below shows test ideas that can be used to create test cases under each of the hats:

Six Thinking Hats


Albert Einstein once said, “We cannot solve our problems with the same thinking we used when we created them.” To solve complex problems and to achieve better results, we need to change the way we think.

Analysing problems from different viewpoints will lead to well-rounded solutions. Six Thinking Hats helps us to look at problems from different perspectives, one by one, and forces us to think outside of our usual thinking style.

Applying six hats principles to exploratory testing will provide structure to ad-hoc tests and enhance test coverage, in turn allowing us to explore innovative test approaches.


Deliver Quality Quicker

At Planit, we give our clients a competitive edge by providing them with the right advice, expert skills, and technical solutions they need to assure success for their key projects. As your independent quality partner, you gain a fresh set of eyes, an honest account of your systems and processes, and expert solutions and recommendations for your challenges.
Find out how we can help you get the most out of your digital platforms and core business systems to deliver quality quicker.


Find out more

Get updates

Get the latest articles, reports, and job alerts.