Free Website Uptime API – JSON for Developers and AI Integrations

Published November 2025 by Site Informant Team

We’re excited to announce the launch of the Site Informant Public API — a simple, free JSON API that lets developers, dashboards, and AI tools access live uptime and SSL data for monitored websites.

Why We Built It

We believe uptime and reliability data should be easy to access, easy to integrate, and easy to automate. Our API provides the same monitoring data we use internally, now available publicly for developers and AI platforms that need real-time status information.

What You Can Do With It

• Build custom dashboards that visualize uptime and response time.
• Feed data into chatbots, Slack bots, or AI agents that monitor site health.
• Automate alerts, notifications, or health summaries in your own systems.
• Use it in research, analytics, or integration projects that need live website reliability data.

How It Works

The API is completely open — no auth keys required. Data is available for sites that have opted into public visibility in Site Informant.

GET https://api.siteinformant.com/api/public/status/prudentdev.com

Example response:

{
  "domain": "prudentdev.com",
  "uptimePercent": 99.89,
  "isOnline": true,
  "lastCheckUtc": "20XX-11-03T07:45:00Z",
  "averageResponseMs": 238,
  "sslExpiresUtc": "20XX-01-04T00:00:00Z",
  "sslIssuer": "Let's Encrypt"
}

The full OpenAPI specification makes it easy for AI tools, plugins, and developers to discover and integrate automatically.

Next Steps

Visit our Developers page for full documentation and C# examples. Try the API yourself — or use it in your own apps, automations, and AI integrations.

Start monitoring for free: Try Site Informant