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Check SSL/TLS Certificate Expiry Dates

Paste a list of domains and MiniMax Converter fetches each site's SSL/TLS certificate, parses the validity dates, and reports how many days until expiry. Colour-coded — green for safe, yellow for warning, red for "fix this now". Same as the daily concerns of any sysadmin running production sites. Free, offline (no third-party SSL-checker service), batch-friendly.

Check SSL/TLS Certificate Expiry Dates — screenshot

What gets checked

For each domain you supply, the tool opens a TLS connection on port 443 (or any port you specify), grabs the certificate chain, and parses: Common Name (CN), Subject Alternative Names (SANs), Not Before + Not After dates, Issuer, Days until expiry. Also flags chain issues (missing intermediates, self-signed certs, mismatched hostnames).

How to use it

  1. Open Tools → Certificates → Inspect → Check expiry.
  2. Paste one domain per line (e.g. example.com, api.example.com:8443 for a non-standard port).
  3. Click Check. Each domain takes ~1-2 seconds; results stream in as they complete.
  4. Sort by days-until-expiry to spotlight the urgent ones. Export as CSV / JSON for a ticketing system or monitoring tool.

Typical alert thresholds

30 days: yellow — start the renewal process. 14 days: orange — urgent. 7 days: red — drop everything. Expired: site is showing a browser warning to every visitor; renew immediately. Thresholds are configurable in the tool.

Questions and answers

Does it work for non-public domains?

Yes — anything you can reach from your machine. Internal hostnames, IPs, non-standard ports all work. The tool just needs network reachability.

Does it follow the certificate chain?

Yes — root, intermediate, and leaf certs are all retrieved and parsed. Chain issues (broken trust path) are flagged.

Can I monitor on a schedule?

Not from this UI — it's an interactive checker. For continuous monitoring, export the CSV and feed it into a cron job + alerter. Or just run this weekly.

How does it compare to ssllabs.com / SSL Labs API?

SSL Labs gives a much deeper analysis (cipher suites, protocols, vulnerabilities). MiniMax checks just expiry + basic chain — fast, batch-mode, no rate limiting. Use SSL Labs for deep audit of individual sites; use this for daily expiry monitoring across many sites.

Related tools

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