Free Developer Tools
Free Developer Tools
Small, focused tools to help you understand and fix errors faster. Every tool is completely free, requires no login, and runs entirely in your browser — nothing you type is uploaded.
Available tools
HTTP Status Code Lookup
Type any HTTP status code and instantly see its name, response class, plain-English meaning, and a link to the full guide with causes and fixes. The fastest way to answer "what does this code mean?" without scrolling a giant table.
Claude Code Prompt Generator
Stuck on a bug? Paste in the error message, stack trace, framework, environment, and what changed. This tool assembles a clean, structured prompt you can drop straight into Claude Code or any AI assistant, so it has the context it needs to find the root cause and propose a fix.
Looking for a specific error?
Browse the full HTTP status code reference, read the in-depth guides (including Cloudflare, Nginx, and browser network errors), or compare confusable codes side by side such as 401 vs 403 and 502 vs 503.