Freedom251 › Code Playground Software
Compiler Explorer
What Compiler Explorer is
Compiler Explorer is a free browser-based development tool from Compiler Explorer, founded in 2012. It lets you edit code online and inspect the output produced by compilers, including assembly. The project README lists support for more than 30 programming languages, with multiple compiler choices for each language. Alongside compiler output, the interface can show LLVM IR, Rust MIR, abstract syntax trees, and control-flow graphs. Controls allow compiled code to be linked and executed. You can share code through a URL, or save and load editor text with browser storage and local files. Libraries can be searched and added by version through Conan, although Windows-based compilers currently do not support libraries. A REST API can compile code to assembly and list compilers. Local-instance instructions and local compiler use are also provided. The service links to CppInsights and Quick-bench, and lists web, API, and self-hosted access.
Who it suits
It suits developers and learners who want to see how source code is transformed by different compilers. Teams needing API access or a self-hosted instance can use those listed options.
What it does well
- Supports 30+ programming languages
- Shows assembly, LLVM IR, Rust MIR, and ASTs
- Runs and links compiled code
- Offers sharing and local-file saving
- Provides REST API and self-hosting instructions
What to know first
- Windows-based compilers do not support libraries
- Claude Explain sends code to Anthropic
- No free trial listed
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Warm fuzzy glow | Patreon supporter membership | $1 a month |
| Super supporter | Patreon supporter membership | $10 a month |
| Coder Karma | Patreon supporter membership | $5 a month |
| Legendary supporter | Patreon supporter membership · Limited (20 remaining) | $50 a month |
As godbolt.org lists them, read 9 Oct 2026. The maker's own page has the final word.
Verdict
Compiler Explorer combines multi-language compilation views, execution controls, sharing, and API access in one free service. Check the Windows library limitation and AI data handling before using it for a particular workflow.
Facts from Compiler Explorer's own pages
- AI feature privacy
- The site says Claude Explain sends source code and compilation output to Anthropic, and that Anthropic does not collect or use the data to train its model. · godbolt.org, 9 Oct 2026
- AI opt-out
- The site says it will not process code with AI when it finds the string "no-ai" in the source or included libraries. · godbolt.org, 9 Oct 2026
- API
- The README says a simple REST API can compile code to assembly and list compilers. · github.com, 9 Oct 2026
- Code execution
- The interface includes controls to link and execute compiled code. · godbolt.org, 9 Oct 2026
- Compilation views
- The interface offers compiler output alongside tools and views such as LLVM IR, Rust MIR, AST, and control-flow graphs. · godbolt.org, 9 Oct 2026
- Founded
- 2012 · godbolt.org, 28 Sept 2026
- Free plan
- Yes · godbolt.org, 20 Sept 2026
- Integrations
- The interface links to CppInsights and Quick-bench as companion tools. · godbolt.org, 9 Oct 2026
- Languages and compilers
- The project README says it supports 30+ programming languages and multiple compilers for each language. · github.com, 9 Oct 2026
- Libraries
- Libraries can be searched and added by version, and the site says they are installed using the Conan package manager. · godbolt.org, 9 Oct 2026
- Library limitation
- The site says Windows-based compilers currently do not support libraries. · godbolt.org, 9 Oct 2026
- Security isolation
- A 2025 article by the creator says compilation and execution run in nsjail sandboxes with Linux namespaces, resource limits, and filesystem isolation. · xania.org, 9 Oct 2026
- Self-hosting
- The project README links to instructions for running a local instance and using local compilers. · github.com, 9 Oct 2026
- Sharing and saving
- Users can share code by URL and save or load editor text using browser storage or local files. · godbolt.org, 9 Oct 2026
- Support
- The project lists Discord, a public mailing list, GitHub issues, and email to Matt as ways to get help. · github.com, 9 Oct 2026
- What it does
- Compiler Explorer lets you edit code in a browser and inspect the compiled output, including assembly. · github.com, 9 Oct 2026
- Who it serves
- The project describes an interactive compiler exploration website for seeing how code looks after compilation. · github.com, 9 Oct 2026
Where Compiler Explorer stands on Freedom251
- Code Playground Software#4 of 58
- Coding Playgrounds#14 of 138