Performance Tools

Cache headers, resource hints and a page weight estimator, with plain explanations of when each one helps.

Tool

Delivery/Cache-Control

Build a Cache-Control header without guessing which directives belong together.

What this does

Safe for a whole year because the filename changes whenever the content does.

Asset type

max-age (seconds)stale-while-revalidate

Cache-Control: public, max-age=31536000, immutable