It was a regular testing day, and I was focused on reproducing a bug that had just been reported. I carefully followed the steps, ready to log my observations. But as I navigated through the app, I accidentally clicked on something unrelated. To my surprise, the application behaved oddly - and I had just uncovered a completely new bug.
This wasn't part of my test case. No automation had flagged it. But this is exactly how real users might behave: exploring unpredictably, clicking where they shouldn't, or rushing through workflows in unexpected ways. That's when I realized the hidden value of ad hoc testing.
What Is Ad Hoc Testing?
Ad hoc testing is an unstructured testing approach where the tester doesn’t follow pre-written test cases. Instead, they explore the application freely, relying on their knowledge, intuition, and creativity to uncover defects. It’s less about “checking boxes” and more about thinking like a user:
What happens if I click this twice?
What if I enter invalid data here?
What if I navigate backward instead of forward?
These questions often reveal issues that scripted or automated tests overlook.
Why It Matters?
Real-World Behavior: Users don’t always follow the “happy path.” Ad hoc testing helps simulate unpredictable behavior.
Finding the Unexpected: Many critical bugs are found by accident — when testers deviate from scripts and experiment.
Fast Feedback: Since it doesn’t require documentation or setup, ad hoc testing is quick and often used in tight deadlines.
How to Do It Well?
Ad hoc testing is often underestimated because it sounds “random.” In reality, it’s a skill. Here are a few tips:
Start with a goal: Even though you’re unscripted, focus on a feature or flow.
Think like a new user: Forget what you know as a tester; act like someone using the app for the first time.
Vary your inputs: Try invalid, extreme, or unexpected data.
Take notes: If you do find issues, document the steps clearly so developers can reproduce them.
Conclusion:
Ad hoc testing is not a replacement for test cases or automation — it’s a complement. It adds creativity, unpredictability, and human intuition to the testing process.
Some of my most valuable bug discoveries didn’t come from carefully planned scripts, but from those moments when I clicked something by accident, or followed a hunch that “this might break.”
At the end of the day, software is built for humans, and humans don’t always follow scripts. That’s why ad hoc testing remains one of the most powerful ways to ensure a truly reliable user experience.
Explore, break, discover:)
ad hoc testing exploratory testing software testing bug discovery QA best practices