Uptime monitoring is the practice of continuously checking whether your website or service is accessible and responding correctly. It's the foundation of any reliability strategy, and yet many teams don't set it up until after their first painful outage. This guide covers everything you need to know to get started.

How Uptime Monitoring Works

At its core, uptime monitoring is simple: a service sends HTTP requests to your website at regular intervals from servers around the world. If the response comes back with a successful status code (like 200), your site is up. If it returns an error (like 500 or times out), your site is down and you get alerted.

Modern monitoring goes beyond simple up/down checks. It measures response time, validates that specific content appears on the page (keyword monitoring), checks SSL certificate validity, verifies DNS records, and tracks performance trends over time.

Why Multi-Region Monitoring Matters

Checking from a single location can't distinguish between your site being down globally versus a regional network issue. Multi-region monitoring checks from servers in different geographic locations simultaneously. If one region reports a failure but others don't, you know it's a localized issue rather than a full outage.

This also eliminates false positives. A momentary network blip between the monitoring server and your site might trigger a false alert from a single location, but it won't affect checks from three other regions.

Check Intervals: 30 Seconds vs. 5 Minutes

The interval between checks directly impacts how quickly you detect problems. At a 5-minute interval, you could be down for nearly 5 minutes before the next check discovers the issue. At a 30-second interval, your maximum detection time drops to half a minute.

For revenue-critical pages, e-commerce checkout, SaaS login, API endpoints, shorter intervals are worth it. For informational pages or lower-priority sites, longer intervals keep costs down without significant risk. The right interval depends on how much each minute of undetected downtime costs you.

Types of Monitors

  • HTTP monitors: check that a URL returns the expected status code and response time
  • Keyword monitors: verify that specific text appears (or doesn't appear) on the page
  • SSL monitors: track certificate expiration and chain validity
  • DNS monitors: detect unauthorized changes to your domain records
  • Domain monitors: alert you before domain registrations expire

Understanding Uptime Percentages

Uptime is commonly expressed as a percentage, but the differences between numbers are more significant than they look:

  • 99% uptime = 3.65 days of downtime per year
  • 99.9% uptime = 8.7 hours of downtime per year
  • 99.99% uptime = 52.6 minutes of downtime per year
  • 99.999% uptime = 5.3 minutes of downtime per year

Each additional "nine" represents a 10x improvement in reliability. Knowing where your site stands helps you set realistic SLAs and identify when you need to invest in better infrastructure.

Getting Started in 60 Seconds

Setting up uptime monitoring doesn't need to be complicated. Enter your URL, choose your check interval and alert channels, and you're done. Start with your most critical pages and expand from there. With a free tier that includes 10 monitors, there's no reason not to start today. See pricing and plans.