index.md

---

title: "CSP: block-all-mixed-content"
slug: Web/HTTP/Headers/Content-Security-Policy/block-all-mixed-content
status:
  - deprecated
browser-compat: http.headers.Content-Security-Policy.block-all-mixed-content

---

{{HTTPSidebar}}{{deprecated_header}}

Warning: This directive is marked as obsolete in the specification: all mixed content is now blocked if it can't be autoupgraded.

The HTTP {{HTTPHeader("Content-Security-Policy")}} (CSP) block-all-mixed-content directive prevents loading any assets over HTTP when the page uses HTTPS.

All mixed content resource requests are blocked, including both active and passive mixed content. This also applies to {{HTMLElement("iframe")}} documents, ensuring the entire page is mixed content-free.

Note: The {{CSP("upgrade-insecure-requests")}} directive is evaluated before block-all-mixed-content. If the former is set, the latter does nothing, so set one directive or the other – not both, unless you want to force HTTPS on older browsers that do not force it after a redirect to HTTP.

Syntax

Content-Security-Policy: block-all-mixed-content;

Examples

Content-Security-Policy: block-all-mixed-content;

<meta http-equiv="Content-Security-Policy" content="block-all-mixed-content">

To disallow http assets on a more granular level, you can also set individual directives to https:. For example, to disallow insecure HTTP images:

Content-Security-Policy: img-src https:

Specifications

Not part of any current specification. Used to be defined in the outdated Mixed Content Level 1 specification.

Browser compatibility

{{Compat}}

See also

• {{HTTPHeader("Content-Security-Policy")}}

• {{CSP("upgrade-insecure-requests")}}

• Mixed content