DarnlySSL checker: is my site’s certificate OK?
Type a domain and see if it’s secure, when the certificate runs out, who issued it and whether www is covered, with a plain fix if anything is wrong.
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Reading the public certificate logs and opening the site. This can take up to 15 seconds.
Example result. Type your own domain above.
- Issued by
- Valid
- Renews
- Hosted on
- Covers
What visitors get
Certificate history
Each bar is one certificate from the public logs. Renewals should overlap, with no gaps.
Technical details
Site not loading at all? The domain checker shows where your domain points and which DNS records are missing.
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How it works
- Type a domain, like yoursite.com. You can paste a full link too.
- We read every certificate issued for it from the public Certificate Transparency logs, then open the site over https, http and www to see what visitors really get.
- You get a big verdict with the days left, who issued it and which names it covers. Anything broken comes with a plain fix and a prompt for your AI agent.
Questions
What is an SSL certificate?
It’s what makes the padlock show and lets your site load over https. Without a valid one, browsers show a full-page “Your connection is not private” warning and most people leave. The modern name is TLS certificate, but everyone still says SSL.
Do I need to renew my certificate?
Almost never by hand. Vercel, Netlify, Cloudflare, GitHub Pages, Lovable and most hosts get free certificates from Let’s Encrypt or Google and renew them on their own, about a third of the way before they run out. If the days left keep dropping under 10, renewal is failing, usually because a DNS record changed.
Why does www give an error when my domain works?
www.yoursite.com is a separate name. It needs its own DNS record and has to be added at your host as a second domain, ideally redirecting to the main one. Until then there is no certificate for it, and people who type www get an error.
My custom domain says “pending” in Vercel. What now?
Vercel only issues a certificate once your DNS points to it. Open Settings, then Domains, copy the exact record it shows (an A record to 76.76.21.21 or a CNAME to cname.vercel-dns.com), add it at your registrar, and wait a few minutes. This checker shows when the certificate appears.
Where does the certificate data come from?
Every trusted certificate is recorded in public Certificate Transparency logs. We read them through crt.sh (with Cert Spotter as a backup) and keep the answer for an hour. The live https check runs each time, from darnly.dev’s server. Nothing about your check is stored.
Why does it say a certificate exists but https doesn’t work?
The certificate can be issued on one host while your DNS points to another, for example after moving from Netlify to Vercel. Check where the domain points with the domain checker, then make sure that host has the domain added.