See every certificate ever issued for your domain
Since 2018 every publicly trusted certificate is logged. That log is a free inventory of your own hostnames — including the ones set up two years ago by someone who has left — and an alarm if a certificate appears that you never asked for.
- Runs from your browser, not our server
- No sign-up
- No watermark
Loading the tool…
How it works
- Type the domain; keep “include subdomains” on.
- Wait — crt.sh can take up to a minute.
- Read the names table (expired, expiring soon, valid) and the issuers; download the CSV.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Why is this useful for a small company?
Three reasons: it lists subdomains you may have forgotten (test., old., staging.) that still resolve and may run old software; it shows expiry dates so nothing lapses; and an unexpected certificate for your domain is an early sign of a compromised DNS or a mistaken issuance. All from public data.
Why does it sometimes fail or take a minute?
crt.sh is a free, volunteer-run service under heavy load. The tool waits up to sixty seconds and retries once; if it still fails, wait a little and try again — the browser is not the problem.
Will it show internal hostnames?
Only names in certificates issued by public CAs. Names on certificates from your own internal CA are not logged. Wildcards appear as *.domain and hide the specific hosts behind them.
What data leaves my browser?
The domain name, sent to crt.sh directly. This site’s server is not involved and keeps no record of the search.