Side-by-side comparisons
The codes and concepts that look alike and behave differently — a 301 against a 302, a 404 against a 410, HTTP against HTTPS. Each page lays the two out side by side, says when to reach for which, and links the tool to check your own site.
301 vs 302 redirect
A 301 is a permanent redirect that passes ranking signals; a 302 is temporary and keeps the old URL indexed. Here is the difference and when each one fits.
302 vs 307 redirect
Both 302 and 307 are temporary redirects. The difference is that a 307 keeps the HTTP method intact, so a POST stays a POST. Here is when that matters.
301 vs 308 redirect
Both 301 and 308 are permanent redirects that pass ranking signals. The 308 preserves the HTTP method, while a 301 may change POST to GET. Here is the choice.
404 vs 410
A 404 means a page was not found; a 410 means it was removed on purpose and will not return. Search engines drop 410 URLs faster. Here is when to use each.
401 vs 403
A 401 means you are not authenticated; a 403 means you are authenticated but not allowed. They look alike but need different fixes. Here is the difference.
502 vs 504
Both 502 and 504 are gateway errors from a proxy. A 502 means a bad reply from the backend; a 504 means no reply in time. Here is how to tell them apart.
HTTP vs HTTPS
HTTPS encrypts traffic between browser and server while HTTP sends it in the clear. HTTPS is the standard for security, trust, and SEO. Here is the difference.
307 vs 308 redirect
Both 307 and 308 preserve the HTTP method when redirecting. The difference is permanence: 307 is temporary, 308 is permanent and passes ranking signals.
403 vs 404
A 404 means the page does not exist; a 403 means it exists but access is refused. Returning the wrong one can hide live pages from search engines.
503 vs 504
A 503 means the server is temporarily unavailable, often by design; a 504 means a proxy got no reply in time. They look alike but mean different things.
Settle it on your own site
Once you know which code you want, check what your site actually returns — trace redirects, read status codes, inspect SSL. No signup.
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