Expiry & change monitoring for your infrastructure
Stop finding out the hard way.
Expired certificates. Lapsed domains. DNS that changed overnight. Jobs that fail in silence. Silens watches them all and warns you before they become an outage — not after.
Start free — no cardFree tools — no account needed
Check a cert / domain
See when any site's TLS certificate and domain registration expire.
Check a domain →Check a URL
See if a page responds, how fast, and whether it contains the text it should.
Check a URL →Blocklist check
See if an IP or domain is on a spam blocklist — the reason email quietly stops arriving.
Check blocklists →Email setup check
Check a domain's SPF, DKIM and DMARC — the records that keep your mail out of spam.
Check email setup →Like what you see? Let Silens watch it for you and alert you before anything expires or changes.
One place for the alerts you only notice when it's too late
| TLS certificate expiry | Get warned 30 / 14 / 7 / 1 days before a certificate expires — with a check that the chain validates and the hostname matches. |
| Domain registration expiry | An expired domain is a worse outage than a dead server. Silens tracks registration expiry and warns you in good time. |
| DNS change detection | Get alerted the moment an A, MX, CNAME or other record is added or removed — an early signal of a misconfigured cutover, or a hijack. |
| URL & content monitoring | Checks that a page responds, fast enough, and contains the text it should — or doesn't contain text it shouldn't (a broken checkout, a defacement). Verifies the content, not just the status code. |
| Scheduled-job monitoring, done right | A dead man's switch for cron/backups — and it verifies the result, not just that the job ran. Send a value (backup size, row count) and Silens alarms if it's out of range. Catches the 0-byte backup, not just the missing run. |
| Blocklist & reputation (coming soon) | Know the moment your domain or mail-server IP lands on a spam blocklist — before your email quietly stops getting delivered. Free checker live now; monitoring on the way. |
Plans
Free
0 /forever
- All the free lookup tools
- Up to 3 job checks
- Missed-ping alarm with grace window
- Email alerts
- Snippet generator (cron, PowerShell, curl)
- Cert & domain expiry monitoring
- DNS change monitoring
- Result verification & anomaly detection
Pro
€7 /month
- Everything in Free
- Cert & domain expiry monitoring (30/14/7/1-day alerts)
- DNS change monitoring (A/AAAA/MX/CNAME/NS/TXT)
- URL & content monitoring (keyword + response time)
- Unlimited job checks
- Result verification & duration anomaly detection
- Webhook alerts