Hey everyone! 
I’m curious to know your thoughts and experiences when testing web applications. Do you prefer headless mode or UI mode for your tests?
Personally, I lean towards UI testing because I love seeing how things actually render and behave in real-time. But I’m open to learning from your experiences too!
Share your insights, pros & cons, or any cool tips you have. Let’s make this a great discussion! 
Great question! I’ve worked with both modes in Katalon Studio, and each has its place.
Personally, I also lean toward UI mode for day-to-day testing. The biggest advantage is visibility—you can actually see how elements render, how flows behave, and quickly spot issues like misalignment, timing problems, or unexpected pop-ups. It’s especially helpful during debugging and while developing new test cases. For dynamic web apps, UI mode gives more confidence because you’re validating the real user experience, not just execution success.
That said, headless mode is great for speed and efficiency. It consumes fewer resources, runs faster, and is ideal for CI/CD pipelines or large regression suites. However, debugging can be harder since you don’t “see” what’s happening, so logs and screenshots become critical.
My approach:
UI mode during development & debugging
Headless mode for scheduled runs (like overnight regression on VM/CI), with screenshots on failure
Overall, I prefer UI for confidence and clarity, but headless is perfect for scaling execution.
Hybrid: Headless for 70% CI/CD runs, UI for 30% visual/debug . Headless excels in speed/resource efficiency for regression/smoke on servers but misses CSS/render issues
It doesn’t matter, tests should be conducted no matter how they are conducted 
@arvind.choudhary Basing on Delivery Headless Testing are very Fast with faster execution
Basing on Visibility and Control UI Testing is Better
Headless Testing is best for performance, scalability, and automation and UI Testing is best for user experience and visual validation. For my Side i prefer UI Testing. Thanks
I prefer UI, because we can observe the behavior, I am exploring headless mode as well.
For faster execution i prefer headless, when i have time i prefer UI mode.
I work with both
I prefer Headless mode, Fast and accurate.
Hey,
I usually go with UI mode for testing because it’s easier to see how everything actually works and looks on the screen. It helps spot layout or interaction issues that might be missed otherwise. I still use headless mode when I need tests to run faster, but I prefer having a clear view of what the user sees.
I’m no expert but I heard that headless mode help with speed and time
I Prefer UI Mode for visuals.
UI/Headed is great for observation, For Automation in longer run Headless is the key.
I use CI/CD so --headless mode.
same, i guess its better
I use both depends on setup, Set dynamically via profiles.
both, just at different stages. UI mode while you’re writing and debugging, headless for CI runs and big regression suites.
Headless won’t catch visual stuff like overlapping elements or busted layouts. UI mode will slow your pipeline to a crawl. So develop in UI, run headless in CI.
i prefer UI Mode
Headless mode is efficient imo
depends on how we want it, as i get screenshot in both.