Open the Network panel and reload a page twice. Select the same static resource after each load.

Look for:

Cache-Control and its freshness lifetime
ETag or Last-Modified
Age, which may reveal time spent in a shared cache
a 304 status after conditional validation
“memory cache” or “disk cache” in the transferred-size column

Developer tools often include a Disable cache option. It works while the tools are open and is useful for comparing cached and uncached behavior.

Be careful when testing. A hard reload, normal reload, disabled cache, and private window can produce different results. Record exactly which one you used.

Quick check

Result

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