Network & Web
REST client, headers inspector, IP geo, CIDR calc, DNS, user-agent parser.
HTTP Status Codes
Complete HTTP status codes reference — all standard codes from 100 to 511 with descriptions, examples, and categories. Look up what 404, 301, 500, 200, 403, and 401 mean. Covers informational, success, redirect, client error, and server error codes.
Open →IP Geolocation Lookup
IP address lookup — find geolocation for any IPv4 address: country, region, city, timezone, ISP, and ASN. Leave the field empty to look up your own public IP. Uses the ipapi.co public API for accurate results.
Open →CIDR / Subnet Calculator
CIDR subnet calculator — enter any IP/mask in CIDR notation (e.g., 192.168.1.0/24) to get network address, broadcast address, subnet mask, wildcard mask, first/last usable host, and total host count. Supports IPv4 subnetting and VPC/cloud network planning.
Open →User-Agent Parser
User-agent parser — paste any browser UA string to extract browser name and version, operating system, device type (mobile/desktop/tablet), and rendering engine. Useful for analytics, server logs, bot detection, and compatibility testing.
Open →HTTP Headers Inspector
HTTP headers reference and inspector. Browse all standard request/response headers (Content-Type, Authorization, Cache-Control, CORS, CSP) with descriptions and examples. Paste a raw HTTP response header block to parse it into structured fields.
Open →URL Parser & Builder
URL parser and builder — decompose any URL into protocol, hostname, port, path, query parameters, and fragment. Edit individual components and rebuild the URL. Handles encoded URLs, relative URLs, and URLs with complex query strings.
Open →cURL Builder
cURL command builder — construct curl commands from a form interface. Enter URL, HTTP method, headers, request body, and authentication. Generates both the curl command and equivalent JavaScript fetch() code. Copy with one click.
Open →DNS Lookup
DNS lookup tool — query A, AAAA, MX, TXT, NS, CNAME, SOA, and PTR records for any domain. Uses Google DNS-over-HTTPS for fast, censorship-resistant results. Useful for checking email deliverability, verifying DNS propagation, and debugging domain configuration.
Open →REST Client
Online REST client — test HTTP APIs directly from your browser. Send GET, POST, PUT, PATCH, and DELETE requests. Add custom headers, request bodies, and Basic/Bearer authentication. View status code, response headers, and JSON response body. No install needed.
Open →Universal Inspector
Universal Inspector — paste any string and instantly detect its format: JWT, JSON, UUID, URL, Base64, hex, IP address, cron expression, SHA hash, SQL, Markdown, YAML, PEM certificate, and 20+ more. Automatically routes you to the correct tool with your input pre-filled. No format knowledge needed.
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