It suits developers who need sampling-based CPU profiling for JavaScript or C++ applications running with Node.js.
Free plan WindowsMacLinuxSelf-hosted
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Best Online Code Documentation and Reference Sites 2026
Online resources for code documentation and reference cover languages, frameworks, runtimes, and web standards. They give developers a place to read technical guidance while writing or maintaining code.
Use this list to compare supported platforms, free-plan availability, and the technology covered. The list is rebuilt nightly, so its order can change.
02
unittest
unittest suits Python developers who need built-in test organization, assertions, discovery, mocks, and command-line execution.
WindowsMacLinux Record4.7 Visit
03
React Developer Tools
Web Record3.0 Visit
04
MDN Web Docs
Record2.8 Visit
05
Vue.js
Web Record2.8 Visit
Before you choose
Check platform support
Check whether each site works on macOS, Linux, Windows, the web, or through self-hosting. Choose the access method that fits your development environment.
Review free access
Some entries provide a free plan. Check the current plan terms before relying on a tool for ongoing reference work.
Match the technology
Select references that cover the language or framework used in your project. The list covers technologies including Angular, Apple development, C++, Dart, Django, Go, Java, Kotlin, web standards, Node.js, and PHP.
Check usage rights
Before reading or modifying code with a tool, review its licence and usage terms.
Questions
Are free plans available on these sites?
Yes. Entries including cppreference.com, DevDocs, Java Documentation, Kotlin Documentation, and MDN Web Docs provide a free plan.
Which platforms do these sites support?
The entries cover macOS, Linux, Windows, web access, and self-hosted setups.
Is this list ranked?
No ranking basis is published for this page. Its order is rebuilt nightly and can change.
What technologies do they cover?
Coverage includes Angular, Apple development, C++, Dart, Django, Go, Java, Kotlin, web standards, Node.js, and PHP.
How often can the order change?
The list is rebuilt nightly, so its order can change between visits.
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