Debugger

The Debugger in Bubble is a built-in tool that lets you inspect your app's workflows and data as they run. It shows you exactly what each step does, what values it uses, and where something goes wrong.

Building in Bubble without the Debugger means guessing why something is broken. With it, you can trace every workflow step, see live data values, and pinpoint errors in seconds instead of hours.

Key Takeaways

• Step-through mode: Pause workflow execution at each action to inspect what is happening before moving to the next step.
• Live data inspection: See the exact values Bubble is using for each element, field, or expression during a test run.
• Error messages: The Debugger surfaces error details that do not appear in the regular app view, helping you fix root causes.
• Preview-only tool: The Debugger is only available in Bubble's preview mode, not in the live deployed version of your app.

What is the Debugger in Bubble?

The Debugger in Bubble is a tool that runs during app preview and lets you pause, step through, and inspect workflows as they execute. It shows each action's inputs and outputs so you can find exactly where a workflow is failing or behaving unexpectedly.

The Debugger appears at the bottom of your screen when you open Bubble's preview mode.

• Slow mode: Automatically pauses between each workflow step so you can follow the execution path at your own pace.
• Step mode: Manually advance through each action one at a time, reviewing the data state at each point.
• Log panel: Shows a running list of all events and workflow triggers that have fired during your testing session.

The Debugger is one of Bubble's most valuable tools for new and experienced builders alike. Learning it early saves many hours of frustration.

How the Debugger Works in Bubble

Open your app in preview mode and click the bug icon in the bottom bar to activate the Debugger. You can then trigger a workflow and watch it execute step by step, with data values shown at each action.

The Debugger runs in real time alongside your app. You interact with your app normally and it captures everything in the background.

• Trigger capture: Every workflow triggered during your session appears in the Debugger log, showing what caused it to run.
• Action detail: Click any action in the log to see the exact inputs Bubble used and what the action returned or changed.
• Conditional evaluation: The Debugger shows whether each condition in a workflow was true or false at runtime.

Understanding how to use Bubble's Debugger properly is the fastest way to move from a broken workflow to a working one.

Why the Debugger Matters for No-Code Apps

The Debugger removes the guesswork from fixing broken workflows. Instead of adding and removing actions blindly to find a bug, you can watch your workflow run in real time and see exactly where the problem appears.

Most Bubble bugs are not logic errors in isolation. They are data errors where the wrong value is passed into an action.

• Data visibility: See the exact record, text, or number that an action receives, not just what you expected to pass it.
• Condition clarity: Understand why a conditional workflow branch was or was not triggered based on real runtime values.
• Time saving: Finding a bug in 5 minutes with the Debugger beats spending 2 hours removing actions one by one.

Every Bubble builder should get comfortable with the Debugger during early projects. The time invested in learning it pays off on every project after.

Common Debugger Use Cases in Bubble

Use the Debugger when a workflow does not trigger, when an action fails silently, when the wrong data is being saved, or when a page shows unexpected results after a user interaction.

The Debugger is not just for errors. It is also useful for understanding what a working workflow is actually doing.

• Silent failures: Some Bubble actions fail without showing an error to the user. The Debugger reveals these invisible failures.
• Wrong data saved: If a field gets the wrong value, the Debugger shows what value was actually passed to the "Make changes to" action.
• API debugging: When an API call returns unexpected data, the Debugger shows the raw response so you can trace the issue.

Using the Debugger regularly, even when things seem to work, helps you build with confidence and catch edge-case issues before users do.

Conclusion

The Debugger in Bubble is your primary tool for finding and fixing problems during development. It makes invisible workflow behavior visible, turns guesswork into clarity, and dramatically shortens the time it takes to ship working features. Any serious Bubble project benefits from a developer who knows the Debugger well. At LOW/CODE Agency, we've helped 450+ clients build and scale apps on Bubble and other no-code platforms. Our clients include global brands like Medtronic, American Express, Coca-Cola, Zapier, and Sotheby's.

Frequently Asked Questions

What is the Debugger in Bubble?

The Debugger is a built-in tool in Bubble's preview mode that lets you step through workflows and inspect data values in real time.

How do I open the Debugger in Bubble?

Run your app in preview mode and click the bug icon in the bottom toolbar to activate the Debugger panel.

Can I use the Debugger on a live Bubble app?

No. The Debugger only works in preview mode. It is not available in the deployed live version of your app.

What does slow mode do in Bubble's Debugger?

Slow mode pauses execution between each workflow step so you can read the data state before the next action runs.

Why is my workflow not showing in the Debugger?

If a workflow does not appear, it was not triggered. Check your event conditions and confirm the triggering element is being interacted with.

Does the Debugger show database changes in real time?

Yes. Actions that create or modify records show in the Debugger, and you can verify the change in the Data tab afterward.