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/HTTP

Upgrade-Insecure-Requests

The HTTP Upgrade-Insecure-Requests request header sends a signal to the server expressing the client’s preference for an encrypted and authenticated response, and that it can successfully handle the upgrade-insecure-requests CSP directive.

Syntax

Upgrade-Insecure-Requests: 1

Examples

A client's request signals to the server that it supports the upgrade mechanisms of upgrade-insecure-requests:

GET / HTTP/1.1 
Host: example.com 
Upgrade-Insecure-Requests: 1

The server can now redirect to a secure version of the site. A Vary header can be used so that the site isn't served by caches to clients that don’t support the upgrade mechanism.

Location: https://example.com/ 
Vary: Upgrade-Insecure-Requests

Specifications

Specification Status Comment
Upgrade Insecure Requests
The definition of 'upgrade-insecure-requests' in that specification.
Candidate Recommendation Initial definition.

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Upgrade-Insecure-Requests 44 17 48 No 31 10.1
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
Upgrade-Insecure-Requests 44 44 48 32 10.3 4.0

See also

© 2005–2020 Mozilla and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Upgrade-Insecure-Requests