Tools / Network
SSL Certificate Checker
Inspect any domain's SSL certificate — issuer, validity, SANs, chain and TLS version. Reads the certificate chain directly from the server and produces a detailed report on issuer, validity, SANs, TLS protocol version and the negotiated cipher suite.
The certificate behind HTTPS
An SSL/TLS certificate verifies a site’s identity to the browser and encrypts traffic end-to-end. If a certificate expires, browsers show a full-page security warning and most visitors bail out. This tool marks certificates with less than 30 days in orange and certificates with less than 7 days — or already expired — in red.
For a free certificate, Let's Encrypt is the modern standard with 90-day validity that must be auto-renewed. For wildcard and EV certificates in enterprise environments, see KEYDAL’s server security packages.
About SSL certificates
Yes. Let’s Encrypt is a fully-trusted public CA operated by ISRG and recognized by every major browser. Its encryption strength is identical to paid certificates — the only differences are the validation level (DV) and the 90-day lifetime.
DV (Domain Validated) only verifies domain ownership — issued in minutes. OV (Organization Validated) also verifies the legal entity. EV (Extended Validation) is the most thorough check; the old green-bar UI has been removed from modern browsers, but some regulated industries still prefer EV for compliance and trust.
The SAN list enumerates every hostname the certificate is valid for. Modern browsers check the SAN list (not the legacy Common Name) and reject the certificate if the host isn’t listed. Wildcard certificates (*.example.com) only cover a single level of subdomains.
Yes. TLS 1.3 is faster (1-RTT / 0-RTT handshake), removes weak ciphers and mandates perfect forward secrecy. TLS 1.0 and 1.1 are banned by PCI-DSS; TLS 1.2 is the floor and TLS 1.3 is the recommendation.
SSL and server security in one place
Auto-renewing certificates, WAF, DDoS protection and security audits — included.
When should you use SSL Certificate Checker?
The KEYDAL SSL Certificate Checker tool is a browser-based utility that developers, system administrators, SEO specialists and enterprise technology teams use in their daily operations. It requires no installation, is free, and produces results instantly. It is designed so local teams can run audits without connecting to server environments and run analyses without touching production.
Typical scenarios include: post-migration verification, comparing domain or hosting providers, diagnosing customer issues, security auditing (pre-pentest reconnaissance), root-cause analysis of email deliverability problems, validating CDN or proxy configuration, surfacing technical audit data for SEO teams, and rapid information gathering during incident response. You can copy results as text and share them or paste them into internal documentation.
The KEYDAL infrastructure team provides web hosting, VPS, dedicated server management, server hardening, DNS configuration and SSL/TLS deployment services from Türkiye. Beyond these tools, we deliver server setup and operations support across Hetzner, OVHcloud, Contabo, DigitalOcean and Turkish providers.
Your queries are never stored on our servers
KEYDAL tools run stateless: domain names, IPs, URLs or other inputs are not persisted to any database. Logs are kept only for security purposes (rate limiting, abuse detection) and deleted within 30 days. For tools that handle sensitive data (tokens, API keys, JWTs), processing happens entirely in your browser — nothing is sent over the network. See our Privacy Policy for details.
All tools run over HTTPS with TLS 1.3 support. KEYDAL is a Türkiye-based technology company and complies fully with local data-protection regulations (KVKK) and GDPR principles.
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The KEYDAL free tools collection includes DNS lookup, WHOIS lookup, SSL certificate checker, HTTP headers analyzer, IP geolocation, uptime checker, JSON formatter, JWT decoder, Base64 encode/decode, QR code generator, meta tag analyzer and robots.txt tester. All browser-based, free, no installation.
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