01
Pick a runtime
Open /compiler and choose from 80+ languages in the picker. Your code, stdin and args persist per language.
[ DOCS ]
Start in 10 seconds.
The shortest path from zero to a running program — plus answers to the questions every new user asks.
02
Write + Run
Type in the editor, add stdin if your program reads input, then hit Run. Output streams back with exit code and timing.
03
Share the link
Copy the URL — it encodes language, code and inputs. Reviewers open your exact state. No screenshots needed.
Do I need an account?
No. The playground runs anonymously. Accounts unlock saving, history and larger limits on Pro and Classroom.
How do stdin and args work?
Use the stdin panel for piped input and the args field for CLI arguments. Both travel with shared links.
Can I embed CodeLab in my course or blog?
Yes. Use the /compiler URL in an iframe, or talk to us about Classroom embeds with rosters and assignments.
What are the run limits?
Playground runs cap at ~10s. Pro raises timeouts and file sizes; Classroom raises them further with priority queuing.
TRY IT LIVE
Paste your first program.
No install, no config, no credit card.