CoBlocks Get CoBlocks
● CoBlocks is now live

Scratch is better
together.

Build Scratch projects with friends in real time. Share ideas, move blocks, and make something amazing—side by side.

Get CoBlocks ▶ See how it works
Free to use Open source Chrome Web Store
★ Meteor Dash Shared
YML3 editing
move 10 steps
turn ↻ 15 degrees
say Let's build!
when I receive start
when ⚑ clicked
forever
move 8 steps
if on edge, bounce
when backdrop switches
say We did it!
Maya
Leo
⚑■
✦✦·
▲
Sprite🚀🪐
All changes syncedMaya moved 3 blocks
M

Maya joined the project

Leo
The spaceship works! 🚀

Scroll to explore
BUILT FOR MAKING TOGETHER

One project. Every idea.
All in sync.

CoBlocks turns the Scratch editor into a shared creative space—without changing how you already build.

MEET COBLOCKS

Everything your team needs.
Right where you build.

The extension stays out of the way until it is time to invite, share, or talk.

01 · IN THE EDITOR

Your team, inside Scratch.

A CoBlocks button lives in the Scratch toolbar. See who is online, manage collaborators, share block stacks, and open project chat without leaving your work.

  • Online collaborator presence
  • Project chat in one click
  • Shared project backpack
scratch.mit.edu/projects/meteor-dash/editor
ScratchFileEditTutorials
ML2 online
when ⚑ clicked
forever
move 10 steps
say We did it!
✦
🚀
The real CoBlocks browser extension popup showing the friends list, settings, and project shortcutCoBlocks extension popup in dark mode showing friends and project access

Friends, one click awayAdd trusted collaborators and jump to your projects.

02 · THE EXTENSION

Small popup.
Big teamwork.

Connect your Scratch account, manage your friends list, tune chat notifications, and open your shared projects from one friendly little home.

  • Scratch Auth sign-in
  • Light and dark themes
  • Notification controls
03 · YOUR WORKSPACE

Every shared project,
easy to find.

Your CoBlocks workspace brings together projects you own and projects shared with you, so the next session starts exactly where the last one ended.

  • Owned and shared projects
  • Project thumbnails at a glance
  • Jump straight into creating
CoBlocksWorkspace
WORKSPACE

Your CoBlocks projects

Projects you own and projects shared with you.

🚀✦
Meteor DashWith Maya and Leo
🐙●
Ocean ExplorerOwned by you
🏙️☀
Pixel CityWith Noah
Live

Create at the same time

Watch changes appear as they happen. No sending files, no waiting, no wondering who has the latest version.

Live edits
MLY
Together

Bring your crew

Invite Scratch friends, choose who can join, and build ambitious projects as one team.

+ Invite a friendCopy link
In context

Talk where you build

Chat right inside the Scratch editor so ideas, feedback, and celebration stay close to the project.

LLeo This level is so good ✨MMaya Try it now!
Safe

Your work has a safety net

Local recovery copies help protect your project when the connection gets bumpy or the backend is unavailable.

Saved locallyjust now
FROM SOLO TO SQUAD

Start building together
in three tiny steps.

No new editor to learn. CoBlocks meets you right inside Scratch.

01
Add CoBlocksBrowser extension

Add the extension

Use the Chrome Web Store in a supported desktop browser, or follow the Firefox setup guide.

02
Invite collaborators
M

Maya@mayacodes

L

Leo@leomakes

Invite your friends

Open a project and invite the Scratch friends you want beside you.

03
MLY

Make something great

Code, chat, and watch the whole project come alive together.

BUILT-IN PEACE OF MIND

Keep the fun.
Lose the fear.

Connections can drop. Great ideas shouldn't. CoBlocks keeps local recovery copies so your team's work has somewhere safe to land.

Automatic local recovery Clear connection status Rejoin without the panic
Recovery explainedExample
Scratch saveKeep using Save now
Server snapshotUsed to synchronize the project
Local recovery copyStored in this browser profile
Save important workKeep an .sb3 backup too
QUICK ANSWERS

Good questions.
Straight answers.

Yes. CoBlocks is free to use and open source.

Yes. Each collaborator should install CoBlocks so edits and project access can stay in sync.

Yes. Open a Scratch project, use CoBlocks to invite your friends, and keep building in the editor you already know.

No. CoBlocks is an independent open-source project and is not affiliated with Scratch or the Scratch Foundation.

✦✦✦✦

Your next great idea
needs a few more cursors.

Grab your friends. Open Scratch. Build something none of you would make alone.

Get CoBlocks Free · Open source · Built with care for Scratchers