Resources

This page lives in the Monitor area at /monitor/resources. It is not in the sidebar — it is reached by a direct link, or from another page that links to it.

At a glance#

What it does#

Resources rolls up static-asset loading by URL — images, scripts, stylesheets and fonts — with load counts, p75 duration, time to first byte and transfer size, plus a per-row waterfall of the network phases for that asset.

It answers two separate questions that happen to share a table: which assets are slow, and which are heavy. They are not the same list. A large image on a fast CDN is heavy and fine; a small font on a slow third-party host is light and ruinous.

When to use it#

When Page load or LCP is poor and the server is not the problem. Also as a periodic audit — asset weight only ever grows, and nobody notices the individual commits that did it.

Workflow#

1. 1

   Sort by p75 for slow, then by transfer size for heavy

   Two passes over the same table. Fix the slow ones by moving or caching them; fix the heavy ones by compressing or removing them.

2. 2

   Multiply by load count

   An asset loaded on every page carries its cost every time. Weight × frequency is the real cost ranking.

3. 3

   Open the phase waterfall

   It separates connection setup from transfer. Slow setup on a third-party host means the fix is preconnect or self-hosting; slow transfer means the asset is too big.

Permissions and prerequisites#

Web apps only. No configuration needed beyond web performance reporting.

Limits and edge cases#

• Not the same as Network. That page is API calls; this one is static assets. They are deliberately disjoint and neither includes the other.

• Cross-origin assets report limited timing. Without a Timing-Allow-Origin header from the host, phase detail is unavailable — you get the duration but not the breakdown.

• A cached load is fast and still counted. High load counts with low durations usually mean caching is working, not that the asset is free on first visit.

Troubleshooting#

Phase waterfall is empty for a third-party asset. That is the cross-origin timing restriction above, not a capture failure.

An asset I removed is still listed. The window includes historical loads. Narrow the window to confirm it has actually stopped.

Related#

• Monitor overview