How to test a Bubble app in preview mode

To test a Bubble app in preview mode, you click the Preview button in the Bubble editor, which opens your app in a special testing URL where you can interact with the UI, run Workflows, check Data changes, and use the built‑in Debugger. Preview mode uses your Development version of the database, so any data you create or modify stays separate from Live.

What Preview Mode Actually Is

Preview mode is Bubble’s safe environment for testing how your app behaves before publishing it. It loads the current version of your editor changes and connects to the development database. Anything you do here never affects your live users.

• Changes in the editor → instantly reflected in Preview.
• Data created in Preview → stored only in Development data.
• Privacy Rules → still apply, so it mimics real behavior.

How to Enter Preview Mode

You trigger it directly from the editor using the top-right Preview button. Bubble opens a new tab with your app at a URL ending in version-test. That suffix tells you you’re on the Development version.

• Click Preview in the editor.
• Your app loads with your latest unsaved or saved design changes.
• You can navigate your app exactly like a user.

Using the Debugger

When in Preview, you’ll see the Debugger bar at the bottom. This tool helps you inspect elements, watch expressions update, and step through workflows.

• Run next lets you execute each workflow action step by step.
• Inspect shows values of dynamic expressions, states, and data sources.
• Slow mode helps you watch animations or timing-sensitive logic.

// Example: Using "Inspect" in the Debugger
// You click an element → Debugger shows its data source and current state values

Testing Database Changes

Everything you create or modify in Preview appears in the Development database. You can inspect this with the Data tab → App data → Development.

• Create a thing in Preview → refresh Development data to confirm it appears.
• Test workflows that modify things → verify the fields change as expected.

Testing as Different Users

If your app has logins, Preview mode lets you test as any user. You can log in normally, or use “Run as” from the Data tab to impersonate a specific account.

• Click Data → App Data → All Users.
• Choose a user and click Run as to open Preview as them.