Top Alternatives to OnlineOrNot in 2026

DomainPulse.io

★ 2.8

DomainPulse.io is an advanced service designed to help users easily monitor and manage all their domain registrations in one place.

Downtime Cat

★ 1.6

Downtime Cat monitors your website, and if it goes offline, sends you an email so you can fix it fast.

HetrixTools

HetrixTools offers minute-by-minute global uptime monitoring with 15 free monitors, blacklist alerts for IPs and domains, and server resource tracking. Features a user-friendly design, public uptime pages, white label reports, and continuous updates for enhanced functionality.

Hydrozen.io

★ 1.8

Uptime monitoring service with built-in Statuspages.

MonitorBuddy.com

★ 2.8

Don't stress over uptime. Monitor your services for free.

Netumo

★ 1.5

Netumo is a 24x7 Website Uptime monitor with Domain Tracking, so it can let you know when your site is down and back up and let you know when your domain is about to expire. You can get notified through email, SMS, Slack, Microsoft Teams, or Twitter.

OneUptime

★ 2.0

OneUptime is an open-source complete observability platform.

OpenStatus

★ 2.4

OpenStatus is an open source monitoring services with on-call managements.

Phare

★ 1.0

Phare is the all-in-one platform that covers everything you need to run high-quality production websites with uptime monitoring, analytics, security, incident management, and alerting.

PingRobot

★ 2.6

PingRobot is a website monitoring service that alerts you when websites are not operational and when they come back online.

Semonto

★ 2.1

Semonto is an uptime monitoring app that allows you to keep an eye on your websites, servers and apps 24/7. Get notified when something goes wrong so that you can fix it before anyone notices.

Simple Ping

Simple-ping.com | Seamlessly monitor your websites, web applications and servers

SimpleOps

★ 2.7

Performance monitoring simplified. Never let users see your website down or with bad loading speeds. Receive alerts & insights in real-time on health and performance.

Stasis

★ 1.6

Stasis uses machine learning to model normal activity patterns for your website or app, then lets you know if something looks unusual.

TLS Checker

★ 2.4

TLS Checker is a Free TLS / SSL Expiry Monitoring Service which includes Discovery, Inventory and Management of certificates. For Free.

Uptime Monitor

Uptime Monitor monitors your resources using HTTP/HTTPS (highly customizable), TCP, or Ping protocols. It supports multiple notification channels such as SMS, email, Slack, and Discord. In addition, Uptime Monitor can host status pages on your own domain for free.

UpTime.onl

★ 1.1

Simple website availability and uptime monitoring tool. No installation, checks for backend and frontend errors.

UptimeLine

UpTimeLine checks that your websites are online and notifies you in case of downtime. Get up to 20 monitors checked every 5 minutes for free. All HTTP methods, custom body and headers, regex check on response body, SSL certificate monitoring and more.