v135 · network / connectivity

No-Vary-Search support for the HTTP disk cache

Enables the HTTP disk cache to use the No-Vary-Search response header to share a cache entry between URLs that differ only in the query parameters.

concepts

  1. NVS in disk cache

    The raw probe — demonstrates the disk-cache hit on a back-button navigation.

  2. Cache-hit explorer

    The motivating use case from the explainer: tracking params and reorder-tolerant pagination. Type a No-Vary-Search header, hit URLs, watch the same cache entry serve them all.

  3. No-Vary-Search pattern builder

    Toggle key-order, params, and except. The header text and a live table of cache-key matches for seven sample URLs update so you can see exactly which params Chrome will fold together.

  4. URL Normalizer

    Enter a No-Vary-Search header and a base URL. The normalizer shows each of 10 test URLs and whether it would hit or miss the cache, the canonical cache key after stripping ignored params, and how many cache entries are saved. Preset buttons for UTM, fbclid, ref, key-order, and more.

  5. Analytics param filter

    Campaign tracking parameters (utm_*, fbclid, gclid) create thousands of distinct cache keys for the same page. Pick a preset (UTM, fbclid+gclid, all-tracking, key-order, ignore-all), edit the header live, and see how many of the sample URLs collapse to a single cache entry — with each stripped param highlighted in the URL.

why it shipped

It's common for URLs to have query parameters that contain information that is important for technical or business reasons but doesn't change the user experience. When the same resource is fetched a second time with a different value for these parameters, it is often desirable to serve it from the HTTP disk cache rather than downloading it from the origin server again. This can improve responsiveness for the user, and save bandwidth for both the user and developer.

references