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What is it?

The fastest way to Slap Python on your microcontroller!

How does it work?

Code and load, right in the browser.

Plug It In
Click Connect
Write Python
Click Load uses the experimental Web Serial API and CircuitPython’s REPL to load and run code into your microcontroller’s RAM so that you can test, iterate, and experiment quickly and repeatedly.

Once you’re happy with your code, you can export it with a single click and load it by dragging the file into the microcontroller’s USB Mass Storage.

What do I need?

Works in Chrome & Edge

(Even Chromebooks!)

How much does it cost?


(Free during the BETA!)

Try it


  • Edit and load CircuitPython right from your browser
  • Links to CircuitPython Docs and Examples


Free during the BETA

$10 per year

  • Edit and load
  • Open examples right into the editor
  • Manage, store, and share multiple projects
  • Access to new features as they are developed


Free during the BETA

$30 for 50 students per year

$50 for 100 students per year

$100 for 200 students per year

  • Access to all features for your students
  • Register with a .k12 or .edu email, or apply with a school ID
How do I start?