Website still showing the old version? Check the cache
Find outdated HTML, CSS or images by reading Cache-Control, ETag and 304 responses in your browser’s Network panel.
Find which file is stale
Current HTML can still request an old stylesheet. Old HTML can also reference a previous file name. In DevTools → Network, open the document and the relevant asset separately. Note Cache-Control, ETag and Age if present. A 200 status alone does not prove the origin served the response; the browser or CDN can reuse it.
Understand the cache directives
max-age=600 gives the response a freshness lifetime of 600 seconds. no-cache requires validation before reuse. no-store instructs caches not to store the response. Long freshness can work for public assets with versioned URLs. Avoid allowing a shared cache to store personal account responses.
Read ETag and 304 together
If a browser has ETag "v1", it can send If-None-Match with that value. A 304 allows it to reuse the stored body. A changed representation should receive the new body and validator. If validation still returns the old version, check deployment and caching. Disabling the browser cache in DevTools does not disable the CDN cache.
Use versioned URLs for assets
Content-based names such as app.a1b2.css and app.c3d4.css let you cache public assets longer while revalidating HTML. After deploying, confirm that current HTML references the new URL and that it returns the expected body. If requests still reach the old host, investigate the DNS migration.
HTTP headers
See the request headers sent to Astrotor. For response headers on your own site, open the Network panel.
Open the tool