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Programming
OnlineCompiler logo

Compile and run code in 46 languages, with test-case judging and a Judge0-compatible endpoint.

OnlineCompiler API is a free Programming API that requires apiKey authentication, is served over HTTPS and does not support CORS, so it should be called from a server.

Authentication
apiKey
HTTPS
Yes
CORS
No
Category
Programming
Uptime (30 days)
100%
Visit documentation ↗onlinecompiler.io

Online · 1113 msTested Nov 15, 2026 · checked dailyIs it down? Status & uptime

About OnlineCompiler.io

Get an API key and run code in 46 languages with one request, then the reference for run code, run tests, WebSocket, widget, Judge0 and Piston APIs.

Provider
OnlineCompiler.io
Website
onlinecompiler.io ↗

Details from onlinecompiler.io.

Key facts

  • 100% uptime (30 days)
  • HTTPS
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OnlineCompiler API FAQ

Who provides the OnlineCompiler API?

The OnlineCompiler API is provided by OnlineCompiler.io (onlinecompiler.io). Get an API key and run code in 46 languages with one request, then the reference for run code, run tests, WebSocket, widget, Judge0 and Piston APIs.

Is the OnlineCompiler API free?

Yes. The OnlineCompiler API is listed in the Programming category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.

Does the OnlineCompiler API require an API key?

Yes. The OnlineCompiler API uses apiKey authentication, so you need to register for credentials before making requests.

Can I call the OnlineCompiler API from the browser?

Not directly. The OnlineCompiler API does not allow CORS, so call it from a server, serverless function or proxy instead of front-end JavaScript.

Does the OnlineCompiler API support HTTPS?

Yes. The OnlineCompiler API is served over HTTPS, so it's safe to use in production.

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OnlineCompiler on Public APIs

Markdown

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HTML

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