Expansel checks your sites at regular intervals and writes to you as soon as one stops responding, or when its certificate is about to expire.
What is checkedHTTP status of the page, validity and expiry date of the TLS certificate, response time.
WhenEvery 24 hours, every hour or every fifteen minutes depending on your plan.
What triggers an alertThe site does not answer, returns an error, or its certificate is invalid or close to expiry.
SetupNone. Your pages are read from the outside, the way a visitor reads them.
boutique-exemple.fr
Online
99,62 %
Day by day
241 ms
avg
21/0819/09
Response time
172 msavg 243 ms941 ms
HTTPS · exp. 19/02/2027Sample data
Downtime rarely announces itself
A site goes down on a Sunday evening. Nobody notices. On Monday morning a customer calls to say they haven't been able to order since yesterday. In between, visitors went elsewhere and a search engine crawled an error page. The problem isn't the outage: it's how long it took you to hear about it.
What gets checked
The site answers
A real request is sent to your address and the HTTP status is recorded. A 500 error, a blank page or a silent server are all treated the same way: it's an incident.
The HTTPS certificate is valid
The TLS certificate is inspected on every pass: validity, chain of trust, expiry date. You're warned ahead of time, not on the day the browser starts showing a red warning.
Response time is measured
Every check times the response. The thirty-day curve shows gradual slowdowns: the ones you never see coming because they never caused an outright outage.
What you get
An email when the problem appears, a second one when everything is back to normal. Never a reminder in between.
A rate of successful checks over 7, 30 or 90 days, broken down day by day.
A response-time curve, to spot degradation before it turns into downtime.
A printable PDF report, ready to send to a client or keep for your records.
alertes@expansel.com19:00
Alert: boutique-exemple.fr is not responding
The latest check on boutique-exemple.fr did not pass.
Address :
https://boutique-exemple.fr/
Detail :
HTTP 503
Checked at :
19/09/2026 19:00
See the detail
You will get a second email as soon as it is back to normal: nothing to do on your side for that.
Recovered: boutique-exemple.fr is responding again
boutique-exemple.fr is responding normally again. The incident is closed.
Sample data
What it does not do
We do not measure perceived performance: no Lighthouse score, no JavaScript rendering. A site that answers fast but renders badly counts as available.
We do not watch the inside of your server: no CPU load, no disk space, no database. Only what a visitor can observe.
We do not test logged-in journeys: forms, carts and member areas are out of reach for a public check.
The numbers, per plan
Free
Pro
Business
Entreprise
Monitored sites
1
10
50
50 and up
Check frequency
Daily checks
Hourly checks
Checks every 15 min
Checks every 15 min
All three are included in every plan. What changes is the volume and how often the checks run.
Frequently asked questions
How often are my sites checked?
Once a day on the free plan, hourly on Pro, every fifteen minutes on Business. The frequency is stated on each plan and applies as soon as you switch.
Will I get an email for every failed check?
No. One alert goes out when things move from fine to broken, and a second one when they recover. A site that stays down for three days does not produce three hundred emails.
Will I be warned before the certificate expires?
Yes. The certificate is inspected on every pass, and the alert goes out as the deadline approaches, not on the day the browser starts showing your visitors a red warning. An expiry is something you see coming rather than something you discover on a Sunday evening.