the cost is round-trips, not bytes
a 301 or 302 redirect is not free. the browser asks for url a, the server says 'go ask for url b', the browser asks again, and only then does the content start coming down. on a fast desktop connection that is maybe 60 milliseconds. on a tea estate manager opening your site on 3g from a remote garden in upper assam, it can be 600 milliseconds — long enough to feel.
two redirects double that cost. three is most of a second gone before a single byte of html is on the wire. and every hop happens before any caching, any optimisation, any of the work you did to make the page fast actually starts paying off.
what google's crawler counts
google does not crawl every page on your site every day. each domain has a crawl budget — a rough cap on how many requests googlebot will make in a session before it moves on. every redirect costs one request out of that budget and adds zero pages to the index.
on a small site this is invisible. on a tea brand with five hundred sku pages, or a homestay network with eight hundred property pages, it is the difference between everything indexed by friday and half indexed by next month.
the metric that hides slow pages
most tools report 'average page speed' for the final, post-redirect url. if /products redirects to /shop redirects to /shop/all, your dashboard reports the speed of /shop/all and the round-trip cost of the two hops is silent. the pages that are quietly slow are the ones that never show up in the report.
the fix is boring. audit your redirects, replace any 30x chain with a single hop, update internal links to point directly at the final url, and watch one click of latency disappear from every entry path.
how we ship it
every site we ship has one rule about redirects: internal links go to the final url, never to a 30x. we keep redirects where they protect a real user — a renamed page, a moved post, an old marketing slug — and we keep them flat. one hop, never a chain.
if you are not sure where your chains live, screaming frog and chrome devtools both surface them in under five minutes. it is the cheapest performance win in seo.