"Map every old URL to a new one, one by one."

"Map every old URL to a new one, one by one."

Depends on scale — and at scale, one-by-one is how migrations die.

The comparison: explicit 1:1 redirect mapping versus pattern/regex rules. Explicit mapping is precise — this exact old URL goes to this exact new URL — and it's the right call for your few hundred high-value pages where the destination isn't predictable. You do not regex your money pages.

Pattern rules — rewrite /old-blog/(.*) to /articles/$1 — handle the long tail where structure is consistent. Ten thousand URLs, one rule, no spreadsheet.

The disaster is redirecting everything to the homepage with one lazy rule. Google treats a redirect to an irrelevant page as a soft 404 and drops the equity entirely. "It's technically a 301" doesn't save you; relevance of the destination is what carries the signal.

So: 1:1 for the URLs that earn money, patterns for the structured bulk, and a redirect to homepage for nothing.

(Test the regex against a sample export first. A greedy .* that catches your new URLs too will loop traffic into a redirect chain you'll be debugging at 2am.)