v133 · network / connectivity

Remove <link rel=prefetch> five-minute rule

Previously, when a resource was prefetched using <link rel=prefetch>, we ignored its cache semantics (namely max-age and no-cache) for the first use within 5 minutes, to avoid refetching. Now, we remove this special case and use normal HTTP cache semantics.

concepts

  1. Prefetch 5-min Rule Removal

    Removes the legacy 5-minute survival heuristic for <link rel=prefetch>. Prefetched resources now follow standard Cache-Control semantics.

  2. Cache-Control behaviour

    Three Cache-Control values compared (max-age, no-cache, no-store) plus a browser probe. Shows the new behaviour Chrome 133+ aligns with FF/Safari.

  3. Spec matrix & reuse predictor

    Pick a Cache-Control value and an elapsed time; see browser-by-browser whether the prefetch will be reused or refetched — with the legacy 5-min lane called out.

  4. Migration checklist

    9-item interactive checklist for auditing your site's prefetch usage after the 5-minute rule removal. Check off each task — audit prefetch URLs, fix Cache-Control headers, update RUM assumptions, and test on Chrome 133+.

why it shipped

The 5-minute rule was never standardized, not implemented by other browsers, and now as part of an effort to make prefetch interoperable across browsers I would like to align on a behavior that doesn't include this.

references