How to build file uploads in Bubble

The simplest way to build file uploads in Bubble is to place a File Uploader element on the page, let the user pick a file, and then save the uploader’s value into your database using a normal Create a new Thing action. Bubble automatically stores files in its storage and gives you a URL you can save.

Core Idea

In Bubble, a file is just a file field that stores a URL. The actual file is hosted by Bubble automatically when it’s uploaded through a File Uploader or a Multifile Uploader. You don’t manage servers or folders—Bubble handles all the storage, you just save the returned URL.

• File Uploader = lets user upload a single file.
• Multifile Uploader = lets user upload multiple files at once.
• File field type = database field that stores the file URL.
• Upload happens automatically when user selects a file.
• Saving happens when you store the uploader’s value into your database.

How to build it step-by-step

1. Create a database field on your data type (for example, Thing = “Document”). Set the field type to file. If you need multiple files, set it to list of files.

2. Drag a File Uploader onto the page. This element automatically uploads once the user selects a file and exposes a value called File Uploader’s value, which is the file URL.

3. Create a button like “Save File”. Add a workflow → Create a new Document → set Document’s file = File Uploader’s value.

4. For multiple files: use a Multifile Uploader and save Multifile Uploader’s value (a list of file URLs) into a list field.

Optional but important

• Privacy Rules: If you want files protected, add privacy rules on the data type. Bubble will restrict who can access the file URLs.
• Deleting files: When you delete the thing that stores the file URL, Bubble eventually deletes the file from storage.
• File size limits: Set limits in the File Uploader properties (max size in MB).

Example workflow expression

// In "Create a new Document" step
Document's file = File Uploader A's value   // this is the uploaded file URL