HTTP Cache Header Planner
Plan Cache-Control, ETag and max-age headers for any asset type.
About the HTTP Cache Header Planner
Choose an asset type and freshness strategy to get the right Cache-Control, ETag and Vary headers, with an explanation of how browsers and CDNs will behave.
Examples
Example
hashed static assetOutput
YAMLCache-Control: public, max-age=31536000, immutableKeyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Read more
- Understanding CORS errors and how to fix them
Why 'No Access-Control-Allow-Origin header' shows up, what the browser is actually enforcing, and the exact headers that fix each case.
Version 1.0.0 · Updated 2026-08-09 · Runs entirely in your browser