Front-end Playgrounds

✎
CodePen
Front-end playground
 🎶
JSFiddle
JS/HTML/CSS playground
 ⚡
StackBlitz
Web IDE

Online IDEs

📦
CodeSandbox
Online IDE
 💻
Replit
Online IDE & deployment
 ☁
Gitpod
Cloud dev environment
 🖥
GitHub Codespaces
Cloud IDE by GitHub

Language Playgrounds

🔵
TypeScript Playground
TS playground
 ⚙
Rust Playground
Rust playground
 🐧
Go Playground
Go playground
 🔨
Compiler Explorer
Online compiler & assembly viewer
 🔸
Kotlin Playground
Kotlin playground
 🐍
Python Shell
Python playground