OnlineGDB
OnlineGDB is a browser-based IDE for compiling and debugging code with an embedded GDB debugger.
What OnlineGDB is
OnlineGDB is a browser-based IDE for compiling and debugging code with an embedded GDB debugger. Its homepage lists C, C++, Python, PHP, Ruby, C#, OCaml, VB, Perl, Swift, Prolog, JavaScript, Pascal, COBOL, HTML, CSS and JS Code. Debug controls include start, pause, continue, step over, step into and step out, but Python debugging is not supported. Programs run on the service backend, with private account projects and public links or expiring shareable copies. Permanent links require login. Teachers can publish assignments to classes and evaluate submissions. Compilation and text-mode runtime are limited to 10 seconds, memory to 256 MB, and inactive interactive runs stop after 15 minutes. Files, projects and streams have size limits, excess output is truncated, and programs cannot access the internet. The free account is free.
Good
- Supports many programming languages
- Embedded GDB debugging controls
- Private account projects
- Class assignment and grading tools
- Public and expiring share links
Watch out
- Python debugging is unavailable
- Compilation and runtime have 10-second limits
- Programs cannot access the internet
- Free accounts may be deleted after inactivity
Who it suits
It suits learners, teachers and developers who want browser-based compilation, debugging and code sharing. Users should account for execution, storage and network restrictions.
Verdict
OnlineGDB combines multi-language coding, backend execution, debugging and classroom functions in a web interface. Its free account is useful for bounded exercises, while strict runtime, file, output and network limits shape larger projects.
Plans and prices
From OnlineGDB's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free account | Free | 180 days of inactivity may result in account and saved project deletion |
| Premium subscription | Priced on request | Ad-free experience · Monthly, half-yearly or yearly; subscription won't auto-renew |
The facts
Each one read from OnlineGDB's own pages, with the date it was checked.
What it does
- Classroom
- OnlineGDB Docs says teachers can publish programming assignments to a class and evaluate and grade submissions in multiple ways.checked 8 Oct 2026
- Code sharing
- The IDE offers live public links and shareable copies with an expiry option, and says login is required to create forever links.checked 8 Oct 2026
- Compiler versions
- The FAQ lists compiler and debugger versions for C, C++, Python 3, Rust and Fortran, including GCC 11.4.0 for C and GDB 12.1.checked 8 Oct 2026
- Debugging
- The homepage offers debug controls including start, pause, continue, step over, step into and step out; its interface says Python debugging is not yet supported.checked 8 Oct 2026
- Execution limits
- The FAQ states compilation is limited to 10 seconds, text-mode runtime to 10 seconds, memory to 256 MB, and interactive runs stop after more than 15 minutes of user inactivity.checked 8 Oct 2026
- File and output limits
- The FAQ gives a 100 KB per-file limit, a 200 KB project limit and 64 KB limits for stdin, stdout and stderr; excess stdout and stderr are truncated.checked 8 Oct 2026
- Languages
- The homepage lists C, C++, Python, PHP, Ruby, C#, OCaml, VB, Perl, Swift, Prolog, JavaScript, Pascal, COBOL, HTML, CSS and JS Code.checked 8 Oct 2026
- Network restriction
- The FAQ says programs run through the service cannot access the internet.checked 8 Oct 2026
- Privacy
- The privacy policy says the service may collect details such as name, email, social profile ID, IP address and country, and may use third-party services for tracking and advertising.checked 8 Oct 2026
- Private projects
- Yeschecked 20 Sep 2026
- Purpose
- OnlineGDB is a browser-based compiler and debugger; its About page describes it as an online IDE with an embedded GDB debugger.checked 8 Oct 2026
- Saved project privacy
- The terms say projects saved to an OnlineGDB account are private to the logged-in account.checked 8 Oct 2026
- Support
- The contact page invites users to send queries, comments or concerns through a form or email info[at]onlinegdb.com and says it will respond as soon as possible.checked 8 Oct 2026
- Third-party libraries
- The FAQ lists ncurses and LAPACK as supported third-party libraries for C/C++.checked 8 Oct 2026
Money
- Free plan
- Yeschecked 20 Sep 2026
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