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OpenREPL: a free online REPL for 19+ programming languages

November 5, 2026 ยท 3 min read

You want to test a small piece of code. Maybe it is a Python one-liner, a C pointer question or a quick Go loop. But the compiler is not installed on this machine, and setting it up would take longer than the test itself.

OpenREPL fixes that. It is a free, open-source online REPL and code editor that runs in your browser. Open the page, pick a language and start typing.

What is OpenREPL?

OpenREPL is a place to write and run code without installing anything. It works on any device with a browser. You get a REPL and an editor together: type a line and see the result at once, or write a whole file and run it.

It supports 19 languages, including C, C++, Go, Python, Rust, Java, JavaScript, Node.js, TypeScript, Ruby, Perl, Bash, Tcl, SQLite, jq and Assembly.

Who it is for

Beginners can start learning a language on the first day, without fighting an installer. Working developers can check a snippet, try an idea in a language they do not use every day, or reproduce a problem quickly. Teachers can share a link instead of a setup guide.

What you can do

  • Type a line in the REPL and see the result instantly.
  • Write a full file in the editor and run it.
  • Run and debug in one place. Debug starts paused, so you can step through your code.
  • Share a live link to your code.
  • Fork someone else's REPL and make it your own.
  • Pair with another person on the same live link.
  • Practise data structure and algorithm questions for interview preparation.

A 60-second walkthrough

1. Open openrepl.com and pick a language.
2. Type some code.
3. Run it and read the result.
4. Share the link, so someone else can see and run the same code.

The same steps work in every language. Here is "Hello, OpenREPL" in three of them.

Python:

print("Hello, OpenREPL")

JavaScript:

console.log("Hello, OpenREPL");

C:

#include <stdio.h>

int main(void) {
    printf("Hello, OpenREPL\n");
    return 0;
}

Meet Genie

Genie is the AI assistant built into OpenREPL. It reads your code and your terminal, so you do not have to copy and paste them into a chat. Ask it to explain an error, or to fix your code. In agent mode, it can also do tasks for you, such as managing your files.

Free and open source

OpenREPL is free to use, and the code is open source. You can read it, report problems or suggest changes on GitHub at vickeykumar/openrepl.

You can continue as a guest. If you sign in, which is optional, your files are kept between visits and you get more Genie requests.

Try it now

Pick a language at openrepl.com and run your first line. If something is missing or confusing, please tell us. Feedback shapes what we build next.

Frequently asked questions

Do I need an account?
No. You can continue as a guest. Signing in is optional and gives you saved files and more Genie requests.

Is it really free?
Yes. OpenREPL is free and open source.

Which languages are supported?
19 languages, including C, C++, Go, Python, Rust, Java, JavaScript, Node.js, TypeScript, Ruby, Perl, Bash, Tcl, SQLite, jq and Assembly.