HTTP 301 Moved Permanently — When and How to Use Redirects

HTTP 301 Moved Permanently

A 301 redirect tells clients (browsers and search engines) that a resource has permanently moved to a new URL. All future requests should use the new URL.

301 vs 302 vs 307 vs 308

Code	Meaning	Method	SEO
301	Moved Permanently	May change to GET	Passes full link equity
302	Found (Temporary)	May change to GET	Minimal link equity transfer
307	Temporary Redirect	Preserves method	Minimal link equity transfer
308	Permanent Redirect	Preserves method	Passes full link equity

When to Use 301

• Domain migration — Moving from old.com to new.com
• URL restructuring — Changing /blog/post-123 to /articles/post-title
• Protocol upgrade — Redirecting HTTP to HTTPS
• Trailing slash normalization — /about/ to /about or vice versa
• www to non-www — www.example.com to example.com

Redirect Chains

A redirect chain occurs when URL A redirects to B, which redirects to C. Each hop adds latency and search engines may stop following after 3-5 hops. Always redirect directly to the final URL.

Implementation

Nginx:

server {
    return 301 https://new-domain.com$request_uri;
}

Apache (.htaccess):

Redirect 301 /old-page https://example.com/new-page

Next.js (next.config.js):

module.exports = {
  redirects: async () => [
    { source: '/old', destination: '/new', permanent: true }
  ]
};