When should I use immutable?

Pair it with a long max-age (a year is common) on assets whose filename contains a content hash. The browser then skips the conditional revalidation it would otherwise do on a soft refresh.

no-cache vs no-store?

no-cache means a stored copy must be revalidated before use; no-store means do not store at all. no-store wins when the response contains private data that must never sit on disk.

Cache-Control Header Builder

Network

Composes a valid Cache-Control header following RFC 9111. Tick the directives you need (no-cache, no-store, immutable, …), set the freshness windows (max-age, s-maxage, stale-while-revalidate, stale-if-error), and copy the resulting header. Includes four presets covering the most common deployment patterns: immutable static asset, private rendered page, public API response with stale serving, and full no-store.

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Presets

Visibility

Freshness (seconds)

max-ages-maxagestale-while-revalidatestale-if-error

Output

Cache-Control: public, max-age=3600

no-store overrides every other directive — when it's on, only no-transform is also emitted.

How to use

Start from a preset that matches your scenario, then tweak.
Numeric fields take seconds — leave them blank to omit the directive entirely.
Copy the result into your origin server, CDN rule, or framework's response headers.

Frequently asked questions

When should I use immutable?: Pair it with a long max-age (a year is common) on assets whose filename contains a content hash. The browser then skips the conditional revalidation it would otherwise do on a soft refresh.
no-cache vs no-store?: no-cache means a stored copy must be revalidated before use; no-store means do not store at all. no-store wins when the response contains private data that must never sit on disk.

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