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Comparison

Monitoring a domain for free: what the alternatives are worth

Four vendors offer a permanent free plan, and they don't cover the same things at all. One covers fifty sites but ignores certificates. Another covers a single domain. Ours covers five. And there's a fifth route, the one that genuinely costs nothing: doing it yourself.

Free plans taken from the public sites on 12 September 2026 for UptimeRobot, MxToolbox and Site24x7, and on 25 August 2026 for Domains Defender. We publish DomainVigil: our free plan sits in the same table as the others, with its limit written in the same place as theirs.

“Free” doesn't mean the same thing from one vendor to the next

There are three kinds of free on this market, and confusing them costs time. The first is the trial: thirty days at Site24x7 across their whole suite, seven days at Domains Defender. Everything works, then nothing does. The second is the permanently capped tier: the plan stays open indefinitely, but some of the watches are reserved for paid plans.

The third is the permanent tier with nothing missing: every watch, on a small number of domains. That's ours — 5 domains, seven watches, no card and no countdown — and it's also the rarest, because it's the most expensive one for the vendor.

So the question to ask isn't “is it free?” but “what's missing?”. The cards below answer that one: what each plan gives, and the first wall you're going to hit.

What each free plan gives, and where it stops

One card per vendor. The bottom line is the one that counts: the first thing missing, ours included.

  • UptimeRobot

    • Fifty monitors, with no time limit.
    • One check every 5 minutes.
    • HTTP, port, ping and in-page keyword checks.
    • One status page, with no customization.
    • Five integrations, three months of history.

    What's missing

    Certificate, domain expiry and DNS monitoring: their pricing page files them under the paid plans, from Solo up. And no console access for a colleague.

  • Site24x7

    • Up to fifty resources watched for uptime.
    • Downtime alerts by email.
    • Advertised as permanent.
    • A thirty-day trial opens the whole suite, no card required.

    What's missing

    Everything beyond uptime. And when the thirty-day trial ends, the full suite closes back down to this one plan.

  • MxToolbox

    • One domain, one monitor.
    • Two blacklist monitors, thirty lists queried.
    • One check a week.
    • The SuperTool, free and without an account, for diagnosis on demand.

    What's missing

    Everything else about the domain: no certificate, no expiry, no DNS, no uptime. Their first paid plan is $129 a month.

  • DomainVigil

    • 5 domains, with no time limit.
    • All seven watches, no exceptions.
    • One public status page, 30 days of history.
    • 3 copilot diagnoses a month.
    • Our 9 free tools, no account needed.

    What's missing

    The pace: one uptime check every 30 minutes, against 5 minutes at UptimeRobot. No Slack or Discord, no DMARC delegation, one seat.

Domains Defender has no permanent free plan but a seven-day trial, checked on 25 August 2026 — which is why it's absent from the cards above.

What the other free plans do better than ours

On three points their free plan is more generous than ours, and there's no reason to hide it.

  • UptimeRobot covers fifty free monitors against our 5 domains, with a check every 5 minutes against 30 here. For watching uptime on a lot of sites without paying, it's the best on this page.
  • Site24x7 also gives fifty resources for uptime, and above all thirty days of trial across a full observability suite — enough to diagnose an infrastructure in depth before deciding anything.
  • MxToolbox's SuperTool asks for no account and goes further than our tools on anything to do with email.
  • A home-made script has no ceiling, costs nothing forever, and your data never leaves your machine. If you can write it and maintain it, it's a perfectly valid answer.

What our free plan does

Narrow on the number, complete on the scope: the opposite choice to the others, and a deliberate one.

  • Seven watches on 5 domains, with no tier to clear: expiry, the certificate, DNS, uptime, blacklists, security headers and scheduled jobs.
  • Expiry reminders at 60, 30, 14, 7 and 1 day, and tighter thresholds on short-lived certificates so you aren't warned about an automatic renewal that happens on its own.
  • A public status page to show a client, from the free plan on.
  • 3 copilot diagnoses a month, plus an automatic diagnosis that's never deducted when an alert goes up.
  • No card, no countdown, no chasing: the free plan is a plan, not a trial in disguise.

The fifth route: doing it yourself

It deserves writing up properly, because it works. Three standard commands, an hourly trigger, and you have monitoring that's free forever and whose data never leaves your machine.

  1. Domain name expiry is read with a WHOIS or RDAP query to the registry. The date is public, and comparing it with today's takes one line of script.

  2. The certificate's end date is read by opening a TLS connection on port 443 and asking for the dates on the certificate presented. No library needed.

  3. DNS records are read with a query to the resolver. After that, comparing today's answer with yesterday's is enough to spot a change.

  4. Uptime is checked with an HTTP request and a status code. It's the simplest part, and it's also the one the free plans already cover.

What it actually costs

A machine left running, a script to maintain whenever a WHOIS response format changes, and a way of sending a message that doesn't land in junk. None of that is out of reach, and plenty of technical teams have been doing it well for years.

The real cost is elsewhere. A script tells you what's happening at the moment it runs; it doesn't know to stay quiet during an automatic renewal, it doesn't confirm an outage before writing, it has no history to look up when a client disputes something, and above all it has nobody to read its output on a Sunday. The day it breaks silently, nothing will tell you — that's the classic flaw in home-made monitoring, and it always turns up at the worst moment.

How to choose your free plan

If you have a lot of sites and one worry — that they answer — choose UptimeRobot or Site24x7. Fifty monitors for nothing is unbeatable and we don't pretend to beat it.

If you have few domains but answer for them in front of clients, choose ours. 5 domains watched from seven angles beat fifty sites watched from one, when what costs you dearly is a missed renewal date rather than a twenty-minute outage.

And if you can write a script, write it. You'll learn in one evening what these tools actually do, and afterwards you'll know precisely what you're willing to pay for — or not.

Try DomainVigil for free

5 domains free, forever. No card required.

Questions people ask us

Is the DomainVigil free plan time-limited?
No. No time limit, no card, no automatic switch to a paid plan. It covers 5 domains with all seven watches, 30 days of history and one public status page. What paying changes is the pace of the checks, the number of domains, the Slack and Discord channels, and DMARC delegation.
Can you monitor domain expiry for free anywhere else?
Among the plans checked here, no. UptimeRobot files domain expiry under its paid plans, MxToolbox doesn't advertise it, and Site24x7's free plan stops at uptime. That leaves the WHOIS or RDAP query written by hand, which is free and public — which is exactly what our expiry checker does, and it asks for no account either.
How many domains before you should pay for anything?
Below five, no reason to pay at all. Between five and twenty, a well-chosen free plan still holds, even if it means watching only the most sensitive names. Past twenty, the problem is no longer the number of sites but the number of renewal dates: that's where the time spent keeping them starts costing more than the subscription.

The other comparisons