What is an SB3 file?

An SB3 file stores a project created for Scratch 3, including its project data, costumes and sounds. An iPhone or iPad does not treat this project file as a normal video, so it needs a compatible player.

Steps to open an SB3 file on iOS

Save the .sb3 project in the Files app, iCloud Drive or On My iPhone/iPad.
Install and open SB3 File Opener & Player.
Choose the option to import or open a project.
Select the .sb3 file in the Files picker.
Wait for the project to load, then start it with the player controls.

Download SB3 File Opener & Player on the App Store

Opening a file from Safari, Mail or another app

First save the attachment or download to Files. If the Share sheet offers SB3 File Opener & Player, you may also send the file directly to the app. Keeping an original copy in Files makes it easier to retry an import.

If the SB3 project does not load

Confirm that the filename ends in .sb3.
Download the project again if the file may be incomplete.
Make sure your device has enough free storage for the project assets.
Try a smaller project to identify incompatible extensions or unusually large assets.
Do not rename a different file type to .sb3; renaming does not convert it.

Need an Android SB3 player?

See the separate guide for opening Scratch SB3 files on Android.

Independent app notice

SB3 File Opener & Player is independent and is not affiliated with, endorsed by, or sponsored by the Scratch Foundation or MIT. Scratch is a trademark of the Scratch Foundation.