HTTP Status Code

What Is an HTTP Status Code?

An HTTP status code is a three-digit number that a web server returns in response to every request your browser makes. When you visit a URL, the server sends back a status code that tells your browser (and search engines) whether the request succeeded, failed, or needs special handling.

Status codes are grouped into five categories:

• 2xx — Success
  • 200 OK — The page loaded successfully. This is what you want for every page on your site.
• 3xx — Redirection
  • 301 Moved Permanently — The page has permanently moved to a new URL. Transfers 90–99% of SEO value to the new URL. Use this when you change a permalink or migrate your site.
  • 302 Found (Temporary) — The page is temporarily at a different URL. Search engines keep the old URL in their index. Use during maintenance or A/B tests.
  • 307 Temporary Redirect — Similar to 302 but preserves the HTTP method. Used by WordPress for HTTPS redirects.
• 4xx — Client Error
  • 404 Not Found — The page does not exist. This happens when a URL is mistyped, a page is deleted without a redirect, or a link points to a removed page. Too many 404s signal poor site maintenance to Google.
  • 403 Forbidden — The server refuses access. Usually a file permissions issue.
  • 410 Gone — Like 404 but tells search engines the page was intentionally removed and will not come back.
• 5xx — Server Error
  • 500 Internal Server Error — Something broke on the server. In WordPress, this is often caused by a plugin conflict, a broken .htaccess file, or a PHP memory limit issue.
  • 503 Service Unavailable — The server is temporarily down. WordPress maintenance mode sends this code, telling search engines to check back later without hurting your rankings.

HTTP Status Codes in Practice

You encounter status codes most often when troubleshooting WordPress:

• White Screen of Death often returns a 500 error — enable WP_DEBUG to see the actual PHP error behind it
• Deleted pages return 404 — set up a 301 redirect to preserve SEO value
• SSL misconfiguration can cause redirect loops (too many 301/302 redirects)
• Maintenance mode should return 503 (not 200) so Google knows the downtime is temporary

Check your site's status codes in Google Search Console > Pages (shows indexed vs excluded pages with reasons) or use free tools like httpstatus.io to check individual URLs.

Why It Matters

Status codes are how your server communicates with search engines. A 301 tells Google to transfer rankings. A 404 tells Google the page is gone. A 503 tells Google to come back later. Using the wrong code — like serving deleted pages as 200 instead of 404, or using 302 instead of 301 for permanent moves — directly hurts your crawl budget and search rankings. Understanding the basics protects your SEO investment.

Sources

• HTTP Status Codes and What They Mean for SEO — Yoast
• HTTP Status Codes Explained — Semrush