10 Essential Website Health Checks Every Developer Needs

A healthy website is more than one that's simply "up." It loads fast, stays secure, and works for every visitor on every device. Here are ten checks worth running regularly, whether you manage one site or a hundred. Together they cover availability, performance, security, and reliability.

1. Uptime and availability

The foundation. Confirm the site responds with a healthy 200 status from multiple locations, not a 500 error, a timeout, or a redirect loop. Continuous monitoring with alerts is ideal, but a quick manual check tells you the current status in seconds.

2. Response time and TTFB

Speed is a feature. Measure how long the server takes to respond (time to first byte) and how long the full page takes to load. Slow responses hurt conversions and search rankings, and rising response times often precede an outage.

3. SSL/TLS certificate validity

Check that your HTTPS certificate is valid, trusted, and not close to expiring. An expired certificate triggers browser security warnings that drive visitors away instantly. Aim to be alerted at least two weeks before expiry.

4. DNS and domain health

Verify your DNS records resolve correctly and that your domain registration isn't about to lapse. A forgotten renewal or a stray record change is a surprisingly common cause of "the whole site vanished" incidents.

5. Mobile responsiveness

More than half of web traffic is mobile. Confirm the layout adapts to small screens, tap targets are usable, and nothing overflows or overlaps. Google also uses mobile-first indexing, so mobile problems hurt your rankings.

6. Core Web Vitals

Google's Core Web Vitals measure real-world experience:

• Largest Contentful Paint (LCP) — loading speed; aim for under 2.5 seconds.
• Interaction to Next Paint (INP) — responsiveness; aim for under 200 ms.
• Cumulative Layout Shift (CLS) — visual stability; aim for under 0.1.

These directly influence both user experience and search ranking.

7. Broken links and missing pages

Crawl your site for 404s and broken outbound links. Dead links frustrate visitors, waste crawl budget, and quietly erode SEO. Fix or redirect them, and add a helpful custom 404 page.

8. Security headers and mixed content

Check for essential HTTP security headers (such as HSTS, Content-Security-Policy, and X-Content-Type-Options) and make sure an HTTPS page never loads assets over insecure HTTP. Mixed content breaks the padlock and can block resources entirely.

9. Search engine visibility

Confirm search engines can actually find and index you: a valid robots.txt, an up-to-date sitemap.xml, correct canonical tags, and no accidental "noindex" on pages you want ranked. Google Search Console is the best place to verify indexing and catch coverage errors.

10. Backups and recovery

A health check isn't complete without confirming you can recover. Make sure backups run automatically, and, crucially, test a restore now and then. A backup you 've never restored is only a hope, not a plan.

Run the first check now

Start at the top of the list: confirm your site is up and responding right now with WebsitePulseCheck, then work down through performance, security, and SEO. For continuous coverage of uptime, SSL, and response time, the tools below automate most of this checklist for you.