JDoodle Compiler API alternative: what each does better

The short answer

• Stay with JDoodle if you need a language outside our 12, input typed into a program while it runs, several files per program, library installs, compiler or command-line arguments, or a choice of older versions. We don't do any of those yet.
• Switch to OnlineCompiler.io if volume is the problem: 100,000 free runs a month against 20 a day, and Pro at $49 for 1,000,000 a month. Also if you want published run limits, async callbacks on every plan, stdout and stderr kept apart with an exit code, or an MCP server you can use today.

Price at the same volume

JDoodle's API plans sell credits a day: they reset at midnight UTC and unused ones don't carry over. Ours is an allowance per calendar month (UTC). At each JDoodle plan's full daily quota over a 30-day month:

Every paid JDoodle plan works out to about $0.33 per 1,000 runs, and opening a WebSocket, uploading a multi-file project or using internet access costs an extra credit. Pro here is $0.049 per 1,000 at full use. A daily cap also bites on busy days: a class deadline or a contest can use up a day's credits while most of the month goes unused.

Feature by feature

Language versions

Both run current releases. JDoodle is a release ahead on Java, .NET, F# and Rust; we're ahead on Ruby and Haskell. JDoodle's newest version, with its versionIndex in brackets (languages page, 17 Oct 2026):

Moving a JDoodle call

JDoodle's execute endpoint is synchronous, and so is ours, so a call maps one to one. Keep the API key on your server, as you did with the client secret.

curl -X POST https://api.jdoodle.com/v1/execute \
  -H "Content-Type: application/json" \
  -d '{
    "clientId": "YOUR_CLIENT_ID",
    "clientSecret": "YOUR_CLIENT_SECRET",
    "script": "print(input()[::-1])",
    "stdin": "jdoodle",
    "language": "python3",
    "versionIndex": "6"
  }'

curl -X POST https://api.onlinecompiler.io/api/run-code-sync/ \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "compiler": "python-3.14",
    "code": "print(input()[::-1])",
    "input": "jdoodle"
  }'

If you used JDoodle's WebSocket to show results as they arrive, our WebSocket and widget deliver the whole result when the run ends. For async jobs, the async endpoint posts results to your callback URL. To compare outputs against expected answers, see how to build an online judge, or the wider comparison of code execution APIs.

Frequently asked questions

Is JDoodle's Compiler API free?

Yes, up to 20 credits a day. A run costs one credit, and opening a WebSocket, uploading a multi-file project or using internet access each cost one more. Credits reset every day at midnight UTC and unused ones do not carry over.

How much does JDoodle's Compiler API cost?

On 17 October 2026 its pricing page listed Starter at $10 a month for 1,000 credits a day, Growth at $20 for 2,000, Scale at $50 for 5,000, Business at $100 for 10,000, and Volume at $200 to $1,000 for 20,000 to 100,000 a day. Webhooks, a custom SLA and white-label embeds are on the Custom plan.

Does OnlineCompiler.io support interactive input like JDoodle?

No. Standard input is sent with the run, so a program reads everything at once and cannot prompt for more while it runs. If your users type answers into a running program, JDoodle (or a browser runtime such as Pyodide for Python) does that and we do not yet.

Can I use both?

Yes. Send the languages we don't run, and any program that needs interactive input or several files, to JDoodle, and the rest to OnlineCompiler.io. Both are plain HTTP calls, so a small router in your backend is enough.

Does OnlineCompiler.io have an embeddable editor like JDoodle?

Yes. The widget is a script tag and a div, and sites that only take an iframe can use the iframe embed. Both are free, show no ads and need no login for readers, and the widget has a JavaScript API with events. Neither has interactive input.

Is OnlineCompiler.io free for commercial projects?

Yes. The free plan includes 100,000 runs a month and allows commercial use, with no credit card.