Why does my uptime monitor show the site as down when it works in my browser?

Often a firewall, CDN bot protection or rate limit is blocking the monitor's requests while normal visitors get through. Check whether the monitor's IP ranges or user agent are being challenged. The same rules can block Googlebot, so it is worth fixing rather than ignoring.

Should planned maintenance return 200 or 503?

503. It tells search engines the outage is temporary so they come back later instead of indexing the maintenance message. A Retry-After header can indicate when to return. Keep the window short, since prolonged errors can lead to URLs being dropped.

Does a slow site count as an uptime problem?

Most uptime tools record response time, and a steady rise is often an early sign of trouble. For search, very slow server responses can reduce how much Googlebot crawls. Page experience metrics such as Core Web Vitals are a separate topic, better measured with PageSpeed Insights or the Core Web Vitals report in Search Console.

Will an SEO monitor notice if the whole site goes down?

A scan will fail, but a daily SEO check is not the right tool for outages because it may run hours after the site went down. Availability needs its own frequent checks, which is the reason to combine both in one place rather than rely on either alone.

How much does combined uptime and SEO monitoring cost with Deltio?

Everything is included in every plan. Starter covers up to 50 sites for £24 / €29 / $31 a month, or £20 / €24 / $26 a month billed annually. Professional (200 sites) is £49 / €59 / $64 a month and Enterprise (500 sites) is £119 / €139 / $149 a month. There is a 14-day free trial.

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Uptime and SEO Monitoring, in One Place

Uptime and SEO monitoring combined means watching two things about a site together: whether it responds, and whether what it serves is still correct for search engines. Uptime checks catch outages and server errors, but a page with a noindex, a rewritten canonical or a broken sitemap still returns 200, so an uptime tool reports it as perfectly healthy.

In many agencies these live in different tools owned by different people. Hosting sets up uptime alerts, SEO checks happen by hand when traffic falls, and neither side sees what the other saw on the same day.

What each kind of check can see

Failure	Uptime check	SEO check
Server down, timeout, connection refused	Yes	Only indirectly
`500`, `502` or `503` responses	Yes	Only indirectly
Firewall or bot protection blocking requests	Often, as a failed check	Often, as a failed scan
Maintenance page served with `200`	Usually no	Only if it looks for maintenance pages
`noindex` shipped with a release	No	Yes
Canonical pointing to staging or one category	No	Yes
Title or meta description wiped	No	Yes
Sitemap losing URLs	No	Yes
New `Disallow: /` in robots.txt	No	Yes
SSL certificate close to expiry	Depends on the tool	Depends on the tool
GA4 or GTM removed	No	Yes, if it checks tags

The bottom half of that table is the part that costs rankings, and none of it involves the site going down. A site can be up all month and still be losing pages from Google's index.

Downtime does matter for search

Uptime is not irrelevant to SEO. Google's guidance is that a 503 status (optionally with a Retry-After header) is the correct response for planned maintenance, and short periods of 5xx errors generally cause a temporary slowdown in crawling rather than lost rankings. Errors that persist for days are different: Google can start dropping those URLs from the index. Our article on whether downtime hurts SEO covers the detail.

The awkward middle case is the maintenance page. Many CMS maintenance plugins and hosting holding pages return 200 with a short "back soon" message. An uptime check sees a successful response. Googlebot sees a thin page on every URL, and if it stays up long enough, that is what gets indexed.

Why the shared timeline matters

Two separate tools mean two sets of alerts, routed to two places, triaged by different people, or by nobody. The bigger loss is context. As an illustration, if the uptime tool records an outage on the 14th and a separate SEO tool records that the sitemap shrank on the 14th, nobody connects the two unless they happen to read both.

With both signals on one screen, an outage immediately raises the obvious SEO questions: did the recovery deploy change robots.txt, did the templates come back with the right canonicals, is the sitemap complete? A traffic drop gets the reverse treatment, with infrastructure history available straight away. Our website monitoring checklist for agencies lists what belongs on that screen.

What Deltio covers

Deltio monitors uptime and detects maintenance pages, and on a daily cycle it checks each site's sitemap and pages against the previous check. The SEO side covers noindex, robots.txt, canonicals, titles, meta descriptions and H1s, and URLs added to or removed from the sitemap. Around those it watches SSL certificate and domain expiry, marketing tags (GA4, GTM, Meta Pixel) and the cookie consent banner. Alerts go to Slack and email, configured per site, so each client's issues land with the person responsible for that account.

The honest limit is on the SEO side: page and sitemap changes are picked up on the daily cycle, not the minute a deploy finishes. You can run a manual SEO scan after a release when you do not want to wait. If you currently use a pure uptime service, our UptimeRobot alternative comparison shows the difference in scope, and our guide on catching a noindex in production goes deeper on the most common failure in the table above.

To try both kinds of checks on the same client site, you can start a 14-day trial.

Frequently asked questions

Why does my uptime monitor show the site as down when it works in my browser?: Often a firewall, CDN bot protection or rate limit is blocking the monitor's requests while normal visitors get through. Check whether the monitor's IP ranges or user agent are being challenged. The same rules can block Googlebot, so it is worth fixing rather than ignoring.
Should planned maintenance return 200 or 503?: 503. It tells search engines the outage is temporary so they come back later instead of indexing the maintenance message. A Retry-After header can indicate when to return. Keep the window short, since prolonged errors can lead to URLs being dropped.
Does a slow site count as an uptime problem?: Most uptime tools record response time, and a steady rise is often an early sign of trouble. For search, very slow server responses can reduce how much Googlebot crawls. Page experience metrics such as Core Web Vitals are a separate topic, better measured with PageSpeed Insights or the Core Web Vitals report in Search Console.
Will an SEO monitor notice if the whole site goes down?: A scan will fail, but a daily SEO check is not the right tool for outages because it may run hours after the site went down. Availability needs its own frequent checks, which is the reason to combine both in one place rather than rely on either alone.
How much does combined uptime and SEO monitoring cost with Deltio?: Everything is included in every plan. Starter covers up to 50 sites for £24 / €29 / $31 a month, or £20 / €24 / $26 a month billed annually. Professional (200 sites) is £49 / €59 / $64 a month and Enterprise (500 sites) is £119 / €139 / $149 a month. There is a 14-day free trial.