Network & web tools

Subnet maths, URL parsing and header inspection in the browser.

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Network work is arithmetic that is easy to get wrong by one bit and awkward to redo. How many usable addresses does a /27 hold, where does the next non-overlapping block start, which parts of a long URL are actually query parameters, what is a response header telling you about caching. These tools do that arithmetic and that parsing locally, which keeps internal addressing plans and private URLs off other people's servers.

Tools in this category

CIDR / Subnet Calculator Full subnet breakdown from any CIDR notation. HTTP Status Codes Reference What every status code means — and how to fix it. URL Parser & Analyzer See and edit every component of a URL. UTM Campaign URL Builder Tag marketing links correctly — every parameter explained. IP to Binary Converter See any IPv4 in binary, hex and decimal at once. WebSocket Tester & Debugger Connect, send and inspect WS messages live. .htaccess Redirect Generator Build Apache redirect rules — HTTPS force, www handling & 301 redirects — right in your browser. Apache Virtual Host Generator Generate a production-ready Apache VirtualHost — SSL, PHP-FPM and logging included. Caddyfile Generator Build a clean Caddyfile for static sites, SPAs, reverse proxies or PHP apps in seconds. Cache-Control Header Generator Get the right Cache-Control header for every asset type — presets included, no guesswork. .htaccess to Nginx Converter Translate Apache .htaccess rules into Nginx directives automatically — with honest notes on what needs review. Website Ping Test Measure HTTP response time of any site with repeated rounds

About these tools

Subnets and CIDR, without the off-by-one

A /24 gives 256 addresses but only 254 usable ones, because the first is the network address and the last is broadcast. That subtraction is where most planning errors start. A calculator that shows the network, broadcast, first and last usable host and the total count for any prefix removes the guesswork, and makes it obvious when two ranges you intended to keep separate actually overlap.

Reading a URL precisely

A long URL packs scheme, host, port, path, query and fragment into one string, and percent-encoding hides the boundaries. Parsing it into labelled parts shows which parameters are duplicated, which values were double-encoded, and where a tracking tag was appended twice — all things that are invisible when you are reading the raw string.

Headers explain behaviour

When a page will not cache, a request is blocked by CORS, or a redirect loops, the answer is almost always in the headers rather than the body. Decoding them into plain statements about caching lifetime, allowed origins, content type and security policy turns a wall of key-value pairs into an explanation you can act on.