Network & Web Reference Tools
Inspect URLs, HTTP headers, and IP subnets instantly in your browser. Ensure data privacy with offline-capable network utilities requiring no account.
Why reference web standards offline?
HTTP status codes, MIME types, and URL structure are things developers look up constantly, almost always within the context of debugging a live system, where reaching for a browser tab and searching is a context-switch that breaks flow. Having a fast, searchable, offline-capable reference removes that friction.
The tools in this category are reference utilities and inspectors: a searchable HTTP status code database with usage notes and RFC citations, a URL parser that decomposes any string into its constituent parts, and a MIME type database with extension mappings. All data is bundled with the page, so no API call is made when you search.
Because the reference data is static, these tools are particularly reliable in environments with restrictive network policies (corporate firewalls, air-gapped development environments) where external lookups may be blocked. Load the page once and the full dataset is available in your browser's cache.
No. CapyToolkit bundles all reference data with the page. Searching works entirely offline once loaded.
The data covers all IANA-registered codes and types as of the last site update, and is refreshed when new standards are registered.
No. CapyToolkit doesn't require credentials of any kind. The tools are fully open.
Yes. Because all data is local, these tools work behind corporate firewalls or in air-gapped environments as long as you can access the page once to cache it.
HTTP status codes follow IANA and RFC sources. MIME types follow IANA registration. URL parsing follows the WHATWG URL Standard.
Yes. All reference tools include a search field that filters as you type, with no page reloads and no external API calls.
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