Building a Free Uptime Monitor in Under 30 Minutes (No Paid Tools)

Description and use

Build a free uptime monitor in under 30 minutes with Python and GitHub Actions: a script pings a URL, and GitHub Actions schedules it to run every 5–15 minutes, sending alerts to Discord, Slack, or Telegram via webhooks.

Problem

Personal projects often require uptime monitoring, but paid tools charge per site and frequency, making them costly for simple checks.

Outcome

A fully functional, zero‑cost uptime monitor that runs on GitHub Actions, alerts via popular chat platforms, and requires no dedicated server or paid service.

Workflow

• Create a new GitHub repository
• Add a Python script that sends an HTTP GET to the target URL, checks the status code, and posts a JSON payload to a webhook URL if the check fails
• Store the target URL and webhook URL in GitHub Secrets
• Create a .github/workflows/uptime.yml file with a schedule trigger (cron) and steps to set up Python, install dependencies, and run the script
• Test the workflow by forcing a failure and verifying the alert is received
• Adjust the cron interval as needed (5, 10, or 15 minutes)

Evidence

Check if a site responds, on a schedule. If it doesn't respond, or the response code isn't in the 200 range, send an alert somewhere you'll actually see it — Discord, Slack, or Telegram all work fine with a webhook.

Source

The webhook URL and any other secrets go into the repo's encrypted secrets, not into the script itself, so nothing sensitive ends up committed to the repository.

Source

This isn't a replacement for a proper monitoring tool if you need historical uptime data, multi-region checks, or alerting that escalates through multiple channels if the first one doesn't get acknowledged.

Source