Let's compare some tools to monitor websites. We analyse external website monotring service, as we thing one should (also) monitor from outisde to have a more global view.

Uptime Kuma seems a good self-hosting software. https://github.com/louislam/uptime-kuma

uptimerobot.com - We used and love this tool. The free tier is generous (50 monitors, 5-minute check interval). It is quite simple. Nevertheless, it was recently limited to non-commercial purposes. First paid tier: information not readily available. First plan at 7 USD/month.

statuscake.com - Free plan for personal use (3 sites, 15 min). First paid tier: €16/month. Would have 100,000 users.

betterstack.com - Free tier for personl use (10 monitors, 3-minute checks). First paid tier starts at $29/month.

The following website have no free plan. The price is around 10€/month for the first tier.

pingdom.com - First paid tier starts at $8/month (10 sites, 50 SMS included)

site24x7.com - No free plan. 9€/month for the first plan (25 sites, 1 min).

uptrends.fr - No free tier. Pricing slightly complexe to understand. Around €5/month. Would have 40 000 users.

datadoghq.com - Not sure it is usefull for simple website monitoring.

Which functionnalities are important? We thing the ease of use is fundamental. Then, integration with notification is usefull : SMS/Slack/Telegram. False positive are a real issue. Many tools offer performance and security checks. The length of retained metrics