IP Address Lookup
Look up and classify an IPv4 or IPv6 address with approximate location data from a local privacy-conscious GeoIP database.
Open IP Address LookupWhatWebSees tool suite
Privacy & Browser Tools
Check IP addresses, DNS, websites and browser-visible information with focused tools that explain their results. Local tools stay in your browser; server lookups are bounded to public Internet targets and are not persisted.
IP & Network
IP Address Checker
Validate, normalize and explain an IPv4 or IPv6 address, including public, private, loopback and reserved classifications.
Open IP Address CheckerDNS Lookup
Query common DNS records for a domain, including A, AAAA, CNAME, MX, NS, TXT and SOA records with TTL values.
Open DNS LookupDNSSEC Checker
Inspect DNSKEY and DS records for a domain and understand whether DNSSEC-related records and a parent delegation are observable.
Open DNSSEC CheckerReverse DNS Lookup
Look up PTR hostnames for a public IPv4 or IPv6 address and understand what reverse DNS records mean.
Open Reverse DNS LookupHostname Lookup
Resolve a public hostname to its deduplicated IPv4 and IPv6 addresses with a simple privacy-conscious lookup.
Open Hostname LookupSubnet / CIDR Calculator
Calculate IPv4 or IPv6 CIDR network boundaries, masks, address counts and correct /31 and /32 host semantics.
Open Subnet / CIDR CalculatorDomain RDAP Lookup
Look up public domain registration dates, status, registrar, nameservers and source through the IANA-discovered HTTPS RDAP service.
Open Domain RDAP LookupDomain Age Checker
Estimate a domain's age from its registry-reported RDAP creation date and review expiration and update dates where available.
Open Domain Age CheckerBrowser & Device
User Agent Checker
View your browser's User-Agent, reported platform and available Client Hints with a private, browser-based checker.
Open User Agent CheckerBrowser Checker
Check your browser, platform, language, time zone and other browser-reported details without storing diagnostic values.
Open Browser CheckerScreen Resolution Checker
Check screen resolution, browser viewport, device pixel ratio, color depth and orientation locally in your browser.
Open Screen Resolution CheckerBrowser Privacy Signals
Check browser-reported privacy preferences including Do Not Track, Global Privacy Control and cookie availability.
Open Browser Privacy SignalsWebGL & GPU Checker
Inspect browser-reported WebGL support, renderer, vendor and useful graphics limits without sending GPU details to the server.
Open WebGL & GPU CheckerCanvas Fingerprint Test
Run an explicit, local canvas rendering test and compare a SHA-256 hash without uploading or storing the result.
Open Canvas Fingerprint TestWebsite Diagnostics
Website Status
Check a public website's HTTP status, response time, redirects, final URL and content type using bounded safe requests.
Open Website StatusRedirect Checker
Follow a public HTTP or HTTPS redirect chain safely and inspect every URL, status, Location target, timing and final destination.
Open Redirect CheckerSSL Certificate Checker
Validate a public website's TLS certificate on port 443 and inspect its issuer, names, dates, protocol and cipher.
Open SSL Certificate CheckerServer Headers Checker
Inspect a safe selection of HTTP response and security headers returned by a public website without exposing cookies.
Open Server Headers CheckerSecurity Headers Checker
Inspect CSP, HSTS, Referrer-Policy, Permissions-Policy and cross-origin response headers without assigning a misleading grade.
Open Security Headers CheckerHTTP Headers Checker
See a privacy-conscious selection of HTTP request headers that reached this website through Cloudflare and its reverse proxy.
Open HTTP Headers CheckerRobots.txt Checker
Safely retrieve a site's bounded robots.txt file and inspect its user-agent groups and Sitemap directives.
Open Robots.txt CheckerSitemap Checker
Safely inspect one bounded XML sitemap, identify urlset or sitemapindex documents, and review entry counts, URLs and lastmod values.
Open Sitemap CheckerMeta Tag Checker
Inspect server-delivered title, description, canonical, robots, Open Graph and Twitter metadata from a public web page.
Open Meta Tag CheckerSecurity & Utilities
Email DNS Checker
Inspect a domain's mail routing and published MX, SPF, DMARC and optional DKIM selector records without contacting a mail server.
Open Email DNS CheckerPassword Strength Checker
Check password length and useful strength signals entirely in your browser without transmitting or storing the password.
Open Password Strength CheckerPunycode Converter
Convert Unicode internationalized domain names to ASCII Punycode and decode Punycode domains without a network lookup.
Open Punycode ConverterURL Parser & Analyzer
Parse a URL into its scheme, hostname, port, path, query, fragment and parameters entirely in your browser without requesting it.
Open URL Parser & AnalyzerFile Hash Calculator
Calculate SHA-256, SHA-384 and SHA-512 hashes locally with Web Crypto; your file, filename and hashes never leave the browser.
Open File Hash CalculatorDownload Time Calculator
Estimate ideal file download time from file size and connection speed with clear decimal unit conversions.
Open Download Time CalculatorUseful diagnostics with clear privacy boundaries
Browser and calculator tools run locally whenever possible. Network tools validate inputs, reject non-public destinations, use short timeouts and return only the details needed for the result. WhatWebSees does not create a history of submitted diagnostic values.
Results are snapshots. DNS, certificates, HTTP responses and browser capabilities can change, and location from an IP database is approximate rather than a precise physical position.