Exploratory Testing: Process, Techniques and Examples

Exploratory testing is a hands-on approach where testers learn about the software, design tests, and run them at the same time, rather than working through a fixed sequence of scripted steps. It helps uncover bugs that scripted checks often miss, such as unexpected behaviour and usability problems. This guide covers how it works, the main techniques, a step-by-step process, and when to use it.

What Is Exploratory Testing?

Exploratory testing is a style of software testing where the tester actively investigates the product and uses what they learn to decide what to test next. 

Testers are not restricted to a fixed sequence of predefined test cases, although they may still draw on requirements, checklists, test ideas, or existing test cases as references.

The core idea is that learning, test design, and execution happen together. A tester might notice an odd delay on a form, which raises a question, which leads to a new test, all within minutes.

It is most useful when requirements are incomplete, when a feature is new, when time is short, or when you want to find the kinds of bugs nobody thought to write a test for.

How Does Exploratory Testing Work?

Exploratory testing runs on an adaptive feedback loop:

• Observe how the software behaves.

• Question what you see, and form a hypothesis about it.

• Test the hypothesis with a specific action or input.

• Learn from the result.

• Adjust the next move based on what you found.

A crash might send the tester deeper into one area, while a smooth result might send them somewhere else. This constant feedback keeps the investigation focused on where the risk actually is.

Types of Exploratory Testing

Exploratory sessions vary in how much direction they are given. Some lean on the tester's instincts, some follow user journeys, and others are guided by chosen techniques or a formal session structure. 

Freestyle Exploratory Testing

Freestyle exploratory testing uses minimal upfront structure and relies heavily on the tester's knowledge, observations, and experience. It suits quick checks, early builds, and getting familiar with an unfamiliar product.

Scenario-Based Exploratory Testing

Here the tester explores by following realistic user scenarios or stories, such as "a new customer signs up, adds items to a cart, and applies a coupon." Testers are free to deviate from the scenario when something looks suspicious.

Strategy-Based Exploratory Testing

This type applies specific test design techniques and prior knowledge of the product, such as known weak areas or past defects, to guide exploration. It suits experienced testers who already understand where problems tend to appear.

Session-Based Exploratory Testing

Session-based test management (SBTM) is a structured way of organising and managing exploratory testing, rather than a separate style of testing. It uses a charter, a timebox, session notes, and a debrief. You can apply it to any of the types above.

Exploratory Testing Techniques

The techniques below are applied while exploring. Some, such as error guessing and test tours, are closely tied to exploratory work, while others are general test design techniques used across all kinds of testing.

Error Guessing

Error guessing means using experience to predict where defects are likely to hide. Testers try things that often break software, such as empty fields, special characters, very long text, or repeated clicks on a submit button.

Boundary Value Analysis

Boundary value analysis is a general test design technique that focuses on the edges of allowed input ranges, where bugs tend to cluster. If a field accepts ages 18 to 60, a tester exploring it might try 17, 18, 60, and 61.

Equivalence Partitioning

Equivalence partitioning is another general test design technique. It groups inputs that the system should treat the same way, so you test one representative from each group instead of every value. During exploration, it helps you cover a wide range of inputs without wasting time on near-identical checks.

Heuristics and Test Tours

Heuristics are rules of thumb that guide what to look at. Test tours turn them into themed explorations of the product. Two well-known examples:

• Money tour: Focus on the features that generate revenue or matter most to the business.

• Back-alley tour: Visit the least-used features and rarely visited corners, where neglected bugs often live.

Risk-Based Exploration

Risk-based exploration is a prioritisation approach that decides where to explore first by looking at what could hurt the most: complex features, recent code changes, critical business flows, or areas with a history of defects.

What Is an Exploratory Testing Charter?

A charter is a short mission statement for an exploratory session. It gives the tester a clear focus without dictating exact steps. A commonly used charter format is:

Explore [target] with [resources or conditions] to discover [information].

For example: Explore the profile settings page with different browsers and screen sizes to discover layout and saving issues.

A good charter is narrow enough to finish in one session but open enough to leave room for discovery. If it reads like a step-by-step script, it is too rigid. If it says "test the app," it is too vague.

How to Perform Exploratory Testing Step by Step

Exploratory testing works best when each session has a clear purpose. The steps below take you from preparing for a session to reviewing what you found, and this is the only section that covers the full process.

Understand the Feature and Risks

Start by learning what the feature is supposed to do and who uses it. Read the requirements or user stories, talk to developers or product owners, and note the areas most likely to fail, such as new code, complex logic, or integrations.

Define the Testing Objective

Decide what you want to learn from this session. An objective might be to check how a new payment method handles failures, or to assess whether a redesigned form is easy to use.

Create a Test Charter

Turn the objective into a charter using the format described above, and set a timebox. In session-based testing, 60 to 120 minutes is a common guideline, not a fixed requirement.

Explore and Adapt

Begin testing and follow what you find. When something looks odd, dig into it. When an area seems solid, move on. Vary your inputs, order of actions, and devices, and keep the charter in view so you do not drift too far.

Record Findings and Evidence

Take notes as you go: what you tried, what happened, and any questions that came up. Capture screenshots, recordings, logs, and exact reproduction steps for every bug. Notes written during the session are far more accurate than notes written from memory later.

Review the Session

After the session, review what you covered and what you found. Share results with the team in a short debrief, log the defects, and decide whether follow-up sessions are needed for areas that were only partly explored.

Exploratory Testing Example

Imagine an online store has just added discount codes to its checkout. A tester writes this charter: Explore the checkout page with valid, expired, and stacked discount codes to discover pricing and error-handling problems.

They set a 60-minute timebox and begin. A valid code works as expected. An expired code shows a clear message. Then the tester wonders what happens if a code is applied, the cart is edited, and the code is applied again. The discount stacks twice, and the total drops below the item cost.

Following that lead, they find that removing an item after applying a code does not recalculate the discount, so a customer can get a percentage off items they no longer have. They also notice that the error message for an invalid code disappears too quickly to read.

The tester records screenshots and exact steps for each issue. In the debrief, the team logs three bugs, rates the stacking problem as high priority, and schedules a follow-up session on other payment methods that were not covered.

Exploratory Testing vs Scripted Testing

Exploratory and scripted testing serve different purposes. Exploratory testing adapts as the tester learns more about the product, while scripted testing follows predefined test cases to verify expected behaviour. Most testing strategies use both approaches, depending on the type of risk, feature, and testing objective.

Neither approach is better in every situation, and most strong teams use both. Exploratory testing should not be the only approach for repeatable regression checks, compliance verification, scenarios that need consistent execution, or testing that requires formal evidence. Those areas are better served by scripted or automated tests.

Exploratory Testing vs Ad Hoc Testing

The two terms are often used interchangeably, but they are not the same. Ad hoc testing is generally less structured and less documented, and it is often done without a specific investigation focus.

Exploratory testing may also be flexible, but it is deliberate. The distinction comes down to a few things:

• Intentional learning: the tester is trying to understand the product and its risks.

• Adaptation: each finding shapes the next test.

• A defined focus: there is a clear area or question under investigation, even if it is not a formal charter.

• Useful records: observations and evidence are captured so others can review and act on them.

Formal charters, timeboxes, and debriefs are common in exploratory testing, particularly in session-based approaches, but not every session needs all of them.

Can Exploratory Testing Be Automated?

Traditional exploratory testing relies heavily on human judgement, curiosity, observation, and adaptation, so it is mainly a manual activity. Automation can support parts of the work, such as setting up environments and test data, navigating to a specific state, capturing evidence, repeating actions, and running regression checks. 

When a session uncovers an important bug, you can also turn it into an automated regression test. Newer AI-assisted tools can also perform some dynamic or autonomous exploration. These extend the tester's reach rather than replace human exploratory testing.

Exploratory Testing in Agile

Agile teams work in short cycles with changing requirements, which suits exploratory testing well. Testers can start as soon as a feature is usable, without waiting for detailed specifications or a full set of written test cases, and give fast feedback within the same sprint. Short sessions fit easily into sprint work, and testers and developers can explore together to find and fix issues on the spot.

Benefits of Exploratory Testing

• Finds unexpected bugs and usability problems that scripts can miss

• Requires little preparation, so testing can start early

• Adapts quickly when requirements or features change

• Encourages creative thinking and deeper product knowledge

• Gives fast feedback to developers

Challenges of Exploratory Testing

• Results depend on the tester's skill and product knowledge

• Coverage is harder to measure than with scripted tests

• Sessions are harder to repeat exactly

• Weak note-taking can leave findings unclear or lost

• Without a clear focus, it can drift into aimless testing

Exploratory Testing Best Practices

• Pair testers with developers or other testers to bring different viewpoints.

• Rotate testers across product areas, since fresh eyes notice things familiar ones overlook.

• Prioritise high-risk areas first, such as recent changes and critical business flows.

• Combine exploratory testing with automation so scripts handle repetitive checks and people focus on investigation.

• Share important findings with the wider team, since they often reveal gaps in requirements and design.

AI in Exploratory Testing

AI can assist exploratory testing in several practical ways:

• Suggesting test ideas and charters based on code changes or defect history

• Generating unusual input combinations

• Identifying risky areas of an application

• Helping analyse logs

• Summarising findings and assisting with test documentation

• Autonomously navigating parts of an application to flag crashes, broken links, or visual differences

These capabilities work best as support for the tester, giving broad coverage quickly and leaving the tester more time for deeper investigation.

FAQs 

Who should perform exploratory testing?

Anyone can contribute, but it works best with people who know the product and understand how software fails. Developers, product owners, and designers can also take part and often spot issues testers might miss.

How long should an exploratory testing session be?

In session-based testing, 60 to 120 minutes is a common guideline. The right length depends on the scope of the charter and how long the tester can stay focused.

Does exploratory testing need documentation?

It needs lighter documentation than scripted testing, but not none. At minimum, keep session notes, bug reports with evidence, and a short summary of what was covered.

Do exploratory testers write test cases?

Not in advance, as a rule. Testers usually work from charters, test ideas, and notes instead. Valuable findings can be turned into formal test cases or automated checks afterwards.

When should you use exploratory testing instead of scripted testing?

Choose it when requirements are unclear, a feature is new, time is limited, or you suspect problems that predefined tests would not catch. Use scripted tests for stable, repeatable checks such as regression.