What’s the Best Website Uptime Monitoring Tool?

I am trying to find a simple uptime monitoring setup for my websites and I feel confused. Many tools say they are the best, but most of them look made for big companies. I only want to know when my site goes down and get an alert fast. I do not care about charts or fancy dashboards. I just want a website monitoring tool that works and does its job without stress.

I also care a lot about website uptime history. I want to see past downtime clearly and understand when and why it happened. I have one small VPS, so server uptime monitoring would help me too. I am open to using an uptime monitoring free option if it is reliable. I also checked self hosted monitors, but they look like extra work.

For small websites, which tools did you actually use and trust? I want real experiences, not sales talk.