What is best 3rd party tool to check website uptime?

If i want to know what is my website Uptime overall for last month via some 3rd party tool without paying money. What will be the best tool?

2 recommended

2
Uptime Robot App

Free uptime monitoring service

Ryan Hoover44Founder, Product Hunt · Written
Try Uptime Robot. It monitors your site every 5 minutes for free.
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Basil AbbasFounder and CTO, https://clockit.io · Written
They have a free plan for small businesses.
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Almost too good, I get way too many emails 😆
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