HTTP headers / request & response

Cache-Control

Cache-Control: max-age=300, stale-while-revalidate=60

What it does

The caching rulebook: how long (max-age), where (public/private), and whether to cache at all (no-store). Directives compose to express almost any policy.

The gotcha

no-cache does NOT mean "don't cache" — it means "revalidate before using". no-store is the one that actually prevents storage.

Debugging headers on a phone

The fastest way to see what Cache-Control is actually doing is to send the request and read both sides raw — ReqPad shows auto-generated and custom headers for every request, on all six protocols, with history. Related references: status codes · Content-Type · Content-Length · Connection · X-Request-Id

Inspect Cache-Control on a live request.

Build the request, send it, read raw headers and timing — from your iPhone. Free to start.