OnlineGDB

Free plan Web

What OnlineGDB is

OnlineGDB is a browser-based IDE for compiling and debugging code, with an embedded GDB debugger and a free plan. Its listed languages include C, C++, Python, PHP, Ruby, C#, JavaScript, Swift, and others. Debug controls include starting, pausing, continuing, and stepping through code, but the interface says Python debugging is not yet supported. Projects saved to an account are private to that logged-in account. Users can also share public links or copies with an expiry option; login is required to create links without an expiry. Teachers can publish programming assignments to a class and assess submissions in multiple ways. Execution runs on the backend and is constrained by time, memory, and file and project sizes; programs cannot access the internet. Excess standard output and error are truncated. A free account costs nothing, though accounts and saved projects may be deleted after 180 days of inactivity. The service may collect details such as name, email, social profile ID, IP address, and country, and may use third parties for tracking and advertising.

Who it suits

It suits learners or developers who want to compile code and use debugger controls in a browser. Teachers can use its class assignment and submission evaluation tools.

What it does well

Supports many listed programming languages.
Saved account projects are private to that account.
Teachers can publish assignments and grade submissions.
Public links and expiring shared copies are available.

What to know first

Python debugging is not supported.
Programs cannot access the internet.
Compilation and text-mode runtime are limited to 10 seconds.
Inactivity may lead to account and project deletion.

Plans

Plan	Billed and limits	Price
Free account	180 days of inactivity may result in account and saved project deletion	Free
Premium subscription	Monthly, half-yearly or yearly; subscription won't auto-renew · Ad-free experience	On request

As onlinegdb.com lists them, read 8 Oct 2026. The maker's own page has the final word.

Verdict

OnlineGDB offers browser-based coding and debugging with private account projects and classroom assignment features. Its execution limits, lack of internet access for programs, and unsupported Python debugging are important constraints.

Facts from OnlineGDB's own pages

Classroom: OnlineGDB Docs says teachers can publish programming assignments to a class and evaluate and grade submissions in multiple ways. · docs.onlinegdb.com, 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. · onlinegdb.com, 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. · onlinegdb.com, 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. · onlinegdb.com, 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. · onlinegdb.com, 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. · onlinegdb.com, 8 Oct 2026
Free plan: Yes · onlinegdb.com, 20 Sept 2026
Languages: The homepage lists C, C++, Python, PHP, Ruby, C#, OCaml, VB, Perl, Swift, Prolog, JavaScript, Pascal, COBOL, HTML, CSS and JS Code. · onlinegdb.com, 8 Oct 2026
Network restriction: The FAQ says programs run through the service cannot access the internet. · onlinegdb.com, 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. · onlinegdb.com, 8 Oct 2026
Private projects: Yes · onlinegdb.com, 20 Sept 2026
Purpose: OnlineGDB is a browser-based compiler and debugger; its About page describes it as an online IDE with an embedded GDB debugger. · onlinegdb.com, 8 Oct 2026
Saved project privacy: The terms say projects saved to an OnlineGDB account are private to the logged-in account. · onlinegdb.com, 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. · onlinegdb.com, 8 Oct 2026
Third-party libraries: The FAQ lists ncurses and LAPACK as supported third-party libraries for C/C++. · onlinegdb.com, 8 Oct 2026

Where OnlineGDB stands on Freedom251

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