Cache-Control Header Builder

Build production-ready Cache-Control headers for browsers, APIs, static assets, and CDNs. Toggle directives, tune TTLs, preview behavior, and copy a clean header string without memorizing every caching rule.

Browser + CDN caching Request & response modes Behavior preview Local-only tool

Header builder

Pick a target, tune freshness windows, and enable the directives you actually want.

Freshness windows

Directives

Header modeResponse
Directives0
Fresh for0s
Edge cacheinherit

Preview

RFC-style directives Copied locally Custom scenario

Behavior summary

Choose a preset or set directives to generate a summary.

What this usually means

No header built yet.
No warning yet.

Example server snippet

res.setHeader('Cache-Control', 'public, max-age=300');

Quick guidance

• Use immutable only when the URL changes on content updates. • no-cache does not mean “do not cache.” It means “revalidate before reuse.” • no-store is the blunt hammer for sensitive data. • s-maxage overrides max-age in shared caches like CDNs.