Network & IP tools

Parse a user-agent string into browser, engine, OS, and device type.

Searchable reference of HTTP status codes with meaning and usage guidance.

Look up common HTTP headers and explain pasted raw headers.

Plan Cache-Control, ETag and max-age headers for any asset type.

Parse Set-Cookie headers and flag security issues.

Diff two sets of HTTP headers, case-insensitively.

Trace every redirect hop with status codes, timing and the final URL.

Check HTTP status codes and redirects for many URLs at once.

Calculate network, broadcast, host range, and mask from an IPv4 CIDR.

Expand a CIDR block into individual addresses, or compress a range into CIDR blocks.

Convert IPv4 to decimal/hex/binary, and expand or compress IPv6.

Validate and reformat MAC addresses, and look up the OUI vendor prefix.

Expand an IPv6 address to full form or compress it to shorthand.

Validate and normalise lists of IPv4, IPv6 and CIDR entries offline.

Measure TTFB, page size, compression, caching and resource counts for any URL.

Paste many URLs and save every file one by one, with a pause between downloads.

Convert internationalised domain names to punycode and back.

List every script, stylesheet, image, font and media file a page loads.

Break a URL into protocol, host, port, path, query, and hash.

Convert between URL query strings and JSON, with nested bracket support.

Search well-known TCP/UDP ports and their services.

Searchable reference of DNS record types with examples.

Search file extensions and their MIME types.

Build OAuth 2.0 / OIDC authorization URLs with PKCE support.

Query A, AAAA, MX, TXT, NS, CNAME and other DNS records for any domain.