TCPLab - DNS, WHOIS & SSL Inspector

Inspect the current page's DNS, WHOIS and SSL/TLS in a panel on the right. One click, no tab switching.

TCPLab is a network inspector for the page you are on. Click the toolbar icon to see the site's DNS records, WHOIS registration details and SSL/TLS certificate. FEATURES DNS • View A / AAAA records and TTL. • The first IPv4 / IPv6 address shows its geolocation. • Expand the remaining records by group. • Copy any IP with one click. WHOIS • Registrar, creation and expiry dates, and domain age. • Nameservers, DNSSEC status and readable domain statuses. SSL / TLS • Certificate subject and issuer, validity and SANs. • Public key, TLS version, cipher, ALPN and HTTP/2. • Forward secrecy and the connected IP address. • For HTTP pages, TCPLab checks port 443 and explains this in the UI. QUICK GRADE • S/A/B/C/D/F grade with a 0–100 score. • Based on the certificate, HTTPS/TLS, HTTP/2, IPv6, DNSSEC and domain data. • An invalid certificate caps the grade at C. • If some data is missing, the score is marked as partial instead of being inflated by incomplete data. ICP FILING (CHINESE UI) • On domain pages, TCPLab shows the filing number, entity type and filing entity when available. • A gray badge means not filed or unavailable. • ICP status does not affect the score. HOW TO USE 1. Open any public http:// or https:// page. 2. Click the TCPLab icon. 3. Read DNS, WHOIS and SSL / TLS in the right-side panel. 4. Click the icon again, or the × button, to close it. PRIVACY TCPLab sends only the current page's hostname and the IP addresses returned by DNS to the TCPLab API. It does not send the full URL, query string, page content, cookies or browsing history. The page title is displayed inside the extension only and is not sent to the API. Private and local addresses are filtered before any request is made. NOTES • The grade is a lightweight heuristic based on the data already loaded, not a full security audit. • ICP filing lookup is available only in the Chinese UI and only on domain pages. • TCPLab is not affiliated with the sites you inspect. Website: https://tcp.lc Source and feedback: https://github.com/helloxz/tcplab-extension