demo · v135

No-Vary-Search cache key simulator

A No-Vary-Search response header tells the browser which query params to ignore when matching a cached entry. Chrome 135 finally applies this to the on-disk HTTP cache (not just memory). Type a directive and a set of URLs — the simulator will show which ones would hit the same cache entry.

simulator: works in any browser

No-Vary-Search header value

first fetched URL (the cached one)

computed cache key

—

the code

HTTP/1.1 200 OK
Content-Type: text/html
Cache-Control: max-age=600
No-Vary-Search: params=("utm_source" "utm_medium")

<!-- /article?id=42&utm_source=…  and  /article?id=42&utm_source=other
     now share the same disk-cache entry. -->

computed cache key

the code

see also