Most monitoring tools read the certificate at your endpoint and tell you when it expires. Sematext checks every certificate in the chain — leaf, intermediate and root — alerts at 28, 14, 7 and 3 days on any of them, verifies the issuing authority is the one you expected, and watches for certificate changes every ten minutes. For a monitoring product that is not a dedicated certificate tool, that is remarkable depth.
From $5 a month · No check quotas · Set up in under a minute
Is Sematext Synthetics worth it?
Yes, and it is underrated. Pay-as-you-go at $2 per HTTP monitor with no overage charges is honest pricing, and the certificate handling is better than several products that sell certificates as their entire proposition. The limitations are scale and scope: browser monitors at $7 each get expensive across a large estate, and this is a monitoring component of a wider observability suite rather than a standalone product with a simple story.
Sematext Synthetics runs two kinds of monitor. HTTP monitors check API endpoints, URLs or any HTTP service; browser monitors load the page in a real browser and can walk through user journeys, reporting performance as well as availability.
Pricing is pay-as-you-go per monitor — $2 for an HTTP monitor, $7 for a browser monitor, with a $5 monthly minimum and 30 days of retention. There are explicitly no overage charges, and users and APIs are unlimited. Standard and Pro tiers exist above that with larger allowances and longer retention.
The certificate work is the standout. Certificates are validated on every run, expiry is checked daily with alerts at 28, 14, 7 and 3 days, and the checks cover the leaf, intermediate and root certificates rather than only the one at your endpoint. It also verifies the issuing authority matches what you expect, and HTTP monitors watch for certificate changes every ten minutes with a detailed change report.
Serious certificate handling, on transparent per-monitor pricing.
Leaf, intermediate and root are all checked, with expiry alerts at 28, 14, 7 and 3 days on any of them. An expired intermediate breaks a site as thoroughly as an expired leaf and is far easier to miss.
Alerts if the root or intermediate authority is not the one expected, which catches changes you did not authorise.
HTTP monitors check for certificate changes every ten minutes and report what changed in detail.
$2 per HTTP monitor and $7 per browser monitor, with no overage charges at all.
Seats are not a cost lever, which is unusual at this price point.
Real browser checks covering performance and multi-step user journeys.
Pay-as-you-go per monitor, with a 14-day trial and no credit card.
| Item | Price | Notes |
|---|---|---|
| HTTP monitor | $2 each | API, URL or any HTTP endpoint |
| Browser monitor | $7 each | Real browser, journeys and performance |
| Minimum | $5/month | 30-day retention on pay-as-you-go |
| Standard and Pro | Higher tiers | Larger monitor counts and longer retention |
| Trial | 14 days free | No credit card, no commitment |
Monitoring vendors change plan limits and prices frequently and without announcement. Every figure here carries a "verify on their site" caveat and you should take it seriously before making a decision on cost.
On certificates specifically, Sematext is better than us and we should say so plainly. We read the certificate at your endpoint; they validate the whole chain including intermediates and roots, verify the issuing authority, and detect certificate changes every ten minutes. An expired intermediate is a real outage we would not catch and they would.
Where we differ is flexibility and breadth of monitor type. Our certificate warning window is configurable from 1 to 60 days against their fixed 28, 14, 7 and 3, and we alert both when a certificate has already expired and when the certificate check itself fails. We also cover domain expiry from 1 to 180 days, page content change detection and cron heartbeats, none of which they offer.
On price the models are close enough to be a genuine choice. Twenty-five HTTP monitors with them is $50 a month; twenty-five monitors of any type with us is $5. But their $50 buys chain validation we do not have, so it is not a like-for-like.
The honest split: certificate chains matter most and you have a moderate number of endpoints — theirs. A wider mix of things watched cheaply, with configurable warning windows — ours.
Every recorded change is compared word by word and kept with a before-and-after image. This is the real output, shown with worked example data.
Price fell from $49 to $39, and an annual discount was added.
The item is available again and the basket button returned.
A new subprocessor was added in another jurisdiction.
The free plan sends to one email address. Every paid plan adds the chat and webhook channels below, with 2 to 10 destinations depending on the plan. However many alerts you receive, the price does not change — nothing here is metered or charged per alert.
There are no voice calls and no SMS. If a phone call at 3am is a hard requirement, say so before you subscribe — we would rather tell you now than refund you later.
$2 per HTTP monitor and $7 per browser monitor on pay-as-you-go, with a $5 monthly minimum and 30-day retention. Standard and Pro tiers offer larger allowances. There is a 14-day free trial with no credit card.
Yes. Leaf, intermediate and root are all validated, with expiry alerts at 28, 14, 7 and 3 days on any certificate in the chain. It also verifies the issuing authority matches what you expect.
Browsers reject a connection if any certificate in the chain has expired, not just yours. An expired intermediate takes the site down while your own certificate looks perfectly healthy, and most monitors only read the leaf.
Yes, HTTP monitors check every ten minutes and produce a detailed change report. That catches a certificate replaced without anyone mentioning it.
HTTP monitors check endpoints and APIs at $2 each. Browser monitors load the page in a real browser, covering performance and user journeys, at $7 each.
No. Sematext states explicitly that there are none, which is unusual in a category where metered overages are the norm.
30 days on pay-as-you-go, with longer retention on the Standard and Pro tiers.
Their certificate handling is deeper than ours — full chain, authority verification and change detection, none of which we do. Our warning windows are configurable from 1 to 60 days, we alert on already-expired certificates and failed checks, and we add domain expiry, page content changes and heartbeats from $5 a month.
Last updated August 2026 · Written by Amit Gupta, founder of MonitoringDaddy
Sematext validates certificate chains more deeply than we do. We cover more kinds of monitor for less.