Certly is described as 'Monitors SSL certificates, domain registration expiry, and DNS/DNSSEC across all your sites — and alerts you on Slack, Discord, email, or webhook before anything lapses, so you never find out from your customers' and is a Uptime Monitor service in the network & admin category. There are 2 alternatives to Certly, not only websites but also apps for a variety of platforms, including Android, iPhone, Android Tablet and iPad apps. The best Certly alternative is Uptime Kuma, which is both free and Open Source.
Self-hosted monitoring tool to track uptime via HTTP(s), TCP, Ping, and more with reactive design. Offers 20-second interval checks, notifications through various channels like Webhook, Telegram, supports multiple languages, includes status page and ping charts, aiding small to medium enterprises effectively.
Free real-time monitoring for 50 sites every 5 minutes. Custom alerts through email, SMS, calls, and apps like Slack, PagerDuty, and more. Use status pages and mobile apps for easy management.
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