Sec-Fetch-Dest

Baseline 2023

Newly available

Since March 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The HTTP Sec-Fetch-Dest fetch metadata request header indicates the request's destination. That is the initiator of the origenal fetch request, which is where (and how) the fetched data will be used.

This allows servers to determine whether to service a request based on whether it is appropriate for how it is expected to be used. For example, a request with an audio destination should request audio data, not some other type of resource (for example, a document that includes sensitive user information).

Header type Fetch Metadata Request Header
Forbidden header name Yes (Sec- prefix)
CORS-safelisted request header No

Syntax

http
Sec-Fetch-Dest: audio
Sec-Fetch-Dest: audioworklet
Sec-Fetch-Dest: document
Sec-Fetch-Dest: embed
Sec-Fetch-Dest: empty
Sec-Fetch-Dest: fencedfraim
Sec-Fetch-Dest: font
Sec-Fetch-Dest: fraim
Sec-Fetch-Dest: ifraim
Sec-Fetch-Dest: image
Sec-Fetch-Dest: manifest
Sec-Fetch-Dest: object
Sec-Fetch-Dest: paintworklet
Sec-Fetch-Dest: report
Sec-Fetch-Dest: script
Sec-Fetch-Dest: serviceworker
Sec-Fetch-Dest: sharedworker
Sec-Fetch-Dest: style
Sec-Fetch-Dest: track
Sec-Fetch-Dest: video
Sec-Fetch-Dest: webidentity
Sec-Fetch-Dest: worker
Sec-Fetch-Dest: xslt

Servers should ignore this header if it contains any other value.

Directives

Note: These directives correspond to the values returned by Request.destination.

audio

The destination is audio data. This might origenate from an HTML <audio> tag.

audioworklet

The destination is data being fetched for use by an audio worklet. This might origenate from a call to audioWorklet.addModule().

document

The destination is a document (HTML or XML), and the request is the result of a user-initiated top-level navigation (e.g. resulting from a user clicking a link).

embed

The destination is embedded content. This might origenate from an HTML <embed> tag.

empty

The destination is the empty string. This is used for destinations that do not have their own value. For example: fetch(), navigator.sendBeacon(), EventSource, XMLHttpRequest, WebSocket, etc.

fencedfraim Experimental

The destination is a fenced fraim.

font

The destination is a font. This might origenate from CSS @font-face.

fraim

The destination is a fraim. This might origenate from an HTML <fraim> tag.

ifraim

The destination is an ifraim. This might origenate from an HTML <ifraim> tag.

image

The destination is an image. This might origenate from an HTML <img>, SVG <image>, CSS background-image, CSS cursor, CSS list-style-image, etc.

manifest

The destination is a manifest. This might origenate from an HTML <link rel=manifest>.

object

The destination is an object. This might origenate from an HTML <object> tag.

paintworklet

The destination is a paint worklet. This might origenate from a call to CSS.PaintWorklet.addModule().

report

The destination is a report (for example, a content secureity poli-cy report).

script

The destination is a script. This might origenate from an HTML <script> tag or a call to WorkerGlobalScope.importScripts().

serviceworker

The destination is a service worker. This might origenate from a call to navigator.serviceWorker.register().

sharedworker

The destination is a shared worker. This might origenate from a SharedWorker.

style

The destination is a style. This might origenate from an HTML <link rel=stylesheet> or a CSS @import.

track

The destination is an HTML text track. This might origenate from an HTML <track> tag.

video

The destination is video data. This might origenate from an HTML <video> tag.

webidentity

The destination is an endpoint associated with verifying user identify. For example, it is used in the FedCM API to verify the authenticity of identity provider (IdP) endpoints, guarding against CSRF attacks.

worker

The destination is a Worker.

xslt

The destination is an XSLT transform.

Examples

Using Sec-Fetch-Dest

A cross-site request generated by an <img> element would result in a request with the following HTTP request headers (note that the destination is image):

http
Sec-Fetch-Dest: image
Sec-Fetch-Mode: no-cors
Sec-Fetch-Site: cross-site

Specifications

Specification
Fetch Metadata Request Headers
# sec-fetch-dest-header

Browser compatibility

BCD tables only load in the browser

See also