Uptime Tracker
Uptime Tracker monitors websites, APIs, servers and scheduled jobs around the clock, rechecking failures before sending alerts to help distinguish outages from brief network errors. It supports HTTP(S) and keyword checks, SSL certificates, TCP ports, DNS records, ping, domain expiry, authenticated API tests with JSON assertions, multi-step API workflows, gRPC, SMTP, IMAP and heartbeat monitoring for cron jobs and backups. Alerts can be routed through rules to email, SMS, Slack, Microsoft Teams, Discord, Telegram, Google Chat, PagerDuty, Pushover, ntfy, Gotify, Mattermost, Rocket.Chat and webhooks, with on-call schedules and escalation. The service includes incident timelines, maintenance windows, reports and hosted status pages on custom domains. Individuals, developers, SaaS teams, agencies, freelancers, online stores and small businesses can use it to monitor services and communicate availability. A free plan includes two monitors; paid plans start at $9 per month.
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upsonar.io
Most uptime monitors only check if your server responds. upsonar goes further — it loads your page and discovers every external dependency: CDN-hosted files, third-party scripts, web fonts, and API endpoints. If any of them fail, you get alerted before your users notice.
Availability checks run from multiple global regions simultaneously, so regional CDN failures and localized outages don't go undetected. Beyond uptime, upsonar monitors SSL certificates approaching expiration, tracks domain expiry dates to prevent renewal failures, and detects DNS record changes that could indicate unauthorized modifications.
All five monitoring types work together in one dashboard. Notifications reach you through email, Telegram, or webhooks compatible with Slack, Discord, and PagerDuty. Get started free with 3 websites — all features included, no credit card needed.
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Xitoring
Xitoring is an all-in-one monitoring platform for servers, websites, and status pages. One command installs the Xitogent agent (curl on Linux, MSI on Windows), auto-discovering 30+ services: Nginx, Apache, IIS, MySQL, PostgreSQL, MongoDB, Redis, Docker, RabbitMQ, Kafka, and more.
Monitor CPU, memory, disk I/O, network, and processes, plus uptime checks (HTTP(S), Ping, DNS, TCP, UDP, API, Mail, Heartbeat, Cron) at 1-minute intervals from 15+ global probing nodes. SSL monitoring included.
Alerts via 20+ channels: email, SMS, phone call, WhatsApp, Telegram, Slack, Teams, PagerDuty, Opsgenie, webhooks, and more.
Built-in AIOps answers plain-English questions about your metrics and incidents. The Xitoring MCP server lets Claude, Cursor, or any AI agent read metrics, ack alerts, and manage monitors.
Plus white-label status pages, incident management, REST API, and iOS/Android apps.
Free forever: 2 servers + 8 uptime checks. Paid from $4.99/mo, flat pricing, 30-day trial.
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PagerDuty
PagerDuty, Inc. (NYSE:PD) is a leader in digital operations management. In an always-on world, organizations of all sizes trust PagerDuty to help them deliver a perfect digital experience to their customers, every time.
Teams use PagerDuty to identify issues and opportunities in real time and bring together the right people to fix problems faster and prevent them in the future. PagerDuty's ecosystem of over 350+ integrations, including Slack, Zoom, ServiceNow, AWS, Microsoft Teams, Salesforce, and more, enable teams to centralize their technology stack, get a holistic view of their operations, and optimize processes within their toolsets.
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