Email alerts when an address changes

Tell us an IP address or a domain and we will send you one plain-text email when something about it changes. No account, no dashboard, no newsletter — this is the only mail we ever send, and every message carries the link that stops it.

Nothing is stored beyond a pending row until you click the link in that mail.

What counts as a change

  • A domain resolves somewhere new. The address you are watching was 93.184.216.34, now it is something else — the classic reason to want an alert.
  • The network announcing it changed. The AS number or the organisation that holds the address is different from last time we looked.
  • The registered location moved. The country or city in the geolocation database changed, usually after a database update or a registry transfer.
  • Reverse DNS appeared, changed or disappeared.

We check every confirmed watch about every half hour, read the answer fresh rather than from a cache, and send at most one message per address per day — several changes in one day arrive as one mail listing all of them.

What is stored, and for how long

  • Your email address, the target you asked about, the previous values we compared against, and the timestamps of the last check and the last mail. Nothing else — no IP address of yours, no cookies, no account, no reading history.
  • The request you make right now is counted for rate limiting in memory and thrown away; it is never written to the database.
  • Stopping a watch (the link in every mail, or the button above) deletes the row. It is not flagged as deleted and kept — it is gone.
  • Mail is sent from our own server; we do not hand your address to a marketing platform, and there is nothing to sell.

Why you have to confirm

The first mail asks you to confirm, and the watch only starts after that click. That is what keeps somebody else from typing your address into the form and using us to pester you, and it is also why a typo in your address can never start a watch on somebody's real one.

Want alerts without any server-side storage? The watchlist page keeps a list in your browser only. Prefer to look things up by hand? The tools page has DNS, HTTP and TLS checks that never store anything.


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