Headers: Available-Dictionary

Available-Dictionary header

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The HTTP Available-Dictionary request header allows the browser to specify the best matching dictionary it has to allow the server to use Compression Dictionary Transport for a resource request.

Clients can send an Available-Dictionary header when they support dcb or dcz encodings. The header is a colon-surrounded base-64 encoded SHA-256 hash of the dictionary contents.

See the Compression Dictionary Transport guide for more information.

Syntax

Available-Dictionary: :<base64-hash>:

Directives

<base64-hash>: A base-64 encoded SHA-256 hash of the dictionary contents.

Examples

Accept-Encoding: gzip, br, zstd, dcb, dcz
Available-Dictionary: :pZGm1Av0IEBKARczz7exkNYsZb8LzaMrV7J32a2fFG4=:

Specifications

Specification
Compression Dictionary Transport> # name-available-dictionary>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`Available-Dictionary`	130	130	No	115	No	130	No	86	No	28.0	130	No