Write. Compile.
Run code online.
No installs, no environment to configure. Pick a language from the sidebar, paste your code, and see the output in the same tab — built for quick tests, teaching, and interview practice.
Languages
18Like this tool? Bookmark it with Ctrl+D (Windows/Linux) or ⌘+D (Mac) for instant access next time.
Python
Scripting, data, ML
JavaScript
Web development
TypeScript
Typed JavaScript
Java
Enterprise apps
C++
System programming
C
Low-level programming
PHP
Server-side web
Ruby
Web frameworks
Swift
iOS apps
Kotlin
Android apps
Go
Cloud services
Rust
Safe systems programming
Dart
Flutter apps
Perl
Text processing
Shell
Command scripting
SQL
Database queries
HTML
Page structure
CSS
Styling
No languages match your search.
Which tool do I actually need?
| If you want to... | Use this |
|---|---|
| Check a REST or GraphQL endpoint before wiring it into your app | API Tester |
| Mock an API response while the real backend isn't ready yet | Dummy JSON API |
| Trim word or character count for a meta description or essay | Word Counter |
| Shrink HTML, CSS, or JS before shipping it | Code Minifier |
| See what browser, device, or GPU a visitor is on | Detect My PC |
| Find out if a site is down for everyone or just you | Website Status Checker |
| Work out someone's exact age in years, months, and days | Age Calculator |
| Save a video from YouTube, Instagram, Pinterest, or Twitter | Video Downloaders |
| Track a video's live view count or a channel's subscriber count | YouTube Live Counters |
Built for developers who move fast.
Nothing here is trying to be clever. It's just meant to get out of your way.
Fast execution
Code runs in a sandboxed container the moment you hit Run. Most snippets finish in well under a second.
Isolated & secure
Each run happens in its own disposable container. Nothing you write touches another session, and nothing sticks around after you close the tab.
Works on any device
The editor scales down to a phone screen without losing syntax highlighting or the console panel.
One-click downloads
Export your file with the right extension already attached — .py, .java, .cpp, whatever you were writing.
Instant sharing
Every snippet gets a shareable link automatically — handy for code review or walking someone through a bug.
Free, with no catch
No run limits and no "upgrade to keep going" wall. If that ever changes, it'll be announced here first.
From zero to running in four steps.
Pick a language
Over 20 languages and a few frameworks, from Python to Rust — browse them from the sidebar.
Write
Syntax highlighting, auto-closing brackets, and autocomplete — nothing fancier than that.
Run it
Output shows up in the console panel below the editor, usually within a second or two.
Share or export
Grab a link or download the file — either way, no account needed.
New to coding? Here's how the first few languages compare
| Language | Good first choice if... | Where it's used |
|---|---|---|
| Python | You want readable syntax and fast feedback loops | Scripting, data work, machine learning |
| JavaScript | You're heading toward web development | Browser apps, Node.js backends |
| Java | Your course or job already runs on it | Enterprise backends, Android (alongside Kotlin) |
| C++ | You want to understand memory and performance directly | Systems programming, competitive programming |
Built for the moments when setup gets in the way.
Technical interviews
Spin up any language in seconds instead of setting up a local environment mid-call.
Teaching
Send students a link instead of walking a whole class through an install guide.
Competitive programming
Try an approach in C++ or Python without opening your full IDE.
Quick prototyping
Test whether an idea even works before you commit to a full project setup.
Stop setting up. Start shipping.
No account, no install, no catch — just open a language and start typing.