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Domain probe

Probes 4 min read

Get warned before your domain registration expires, using authoritative RDAP registry data.

What it is

A domain that quietly expires takes your email, website, and APIs down together, and it usually happens because a renewal charge failed while nobody was watching. A Domain probe guards against that. It watches your domain’s registration expiry, the date the domain lapses if nobody renews it, and warns you well before that happens. It reads the date from the authoritative registry over RDAP (the structured successor to WHOIS), so the number comes straight from the source of truth.

This isn’t website monitoring. A Domain probe won’t tell you your server is down; it tells you the domain your whole service depends on is about to lapse. That’s one of the most avoidable outages there is, and one of the easiest to miss.

When to use it

Reach for a Domain probe when

  • You own domains you can’t afford to let lapse: your primary brand, an API domain, an email domain.
  • Auto-renew is on but you don’t fully trust it. Expired cards, registrar transfers, and billing failures all happen.
  • You want weeks of notice, not minutes.

Use a different probe when

  • You want to know whether your site or API is reachable right now. That’s an HTTP probe.
  • You need to check a specific port or service. Use a TCP probe.

How it works

Each check reads your domain’s expiry date from the authoritative registry over RDAP, along with the registrar and domain status. Registries rate-limit heavy querying, so Domain probes run on a slow cadence, hours to days rather than seconds.

Uptimeprobe applies your warn and critical thresholds when it shows status, not when it runs the check, so changing them recolours the whole history right away with no new lookup needed.

Configuring a Domain probe

Create one from Probes, then Add probe, and pick Domain.

FieldWhat it doesNotes
NameA label for the probeRequired, 1 to 255 characters
DomainThe registrable domain to watchJust the domain, like example.com, with no https:// or path
Warn (days)Go Degraded when expiry is within this many daysDefaults to 30
Critical (days)Go Down when expiry is within this many daysDefaults to 7, and must be less than or equal to Warn
IntervalHow often to look it upEvery 12 hours, daily, or weekly

A Domain probe warns you before expiry, it can’t renew for you. Treat a Degraded domain probe as a to-do, not an alert to snooze. Domain probes use a 20-second lookup timeout, and a daily interval is plenty since the expiry date changes at most once a year.

How status is determined

Status comes from the most recent lookup and your day thresholds:

A timeline from today to the domain's expiry date. It stays Up until 30 days out, goes Degraded inside the warn window, and Down inside the 7-day critical window or once expired. The RDAP lookup returns your registration expiry date Up Degraded Down Today Expiry Warn · 30d Critical · 7d
Warn and Critical are day counts before expiry. You set them, and they recolour the whole history the moment you change them.
  • Down: the domain has already expired, the RDAP lookup failed, or expiry falls inside your critical window (7 days by default).
  • Degraded: expiry falls inside your warn window (30 days by default). Time to renew.
  • Up: expiry is comfortably in the future.

Because thresholds apply when status is read, you can widen or tighten Warn and Critical at any time and the timeline updates right away.

Next steps

Create an account and add a Domain probe for every domain you can’t afford to lose. Watching the services on those domains too? Pair it with an HTTP or TCP probe.