Pragma header

The HTTP Pragma header is an implementation-specific header that may have various effects along the request-response chain. This header serves for backwards compatibility with HTTP/1.0 caches that do not support the Cache-Control HTTP/1.1 header.

[!NOTE] The Pragma header is not specified for HTTP responses and is therefore not a reliable replacement for the HTTP/1.1 Cache-Control header, although its behavior is the same as Cache-Control: no-cache if the Cache-Control header field is omitted in a request. Use Pragma only for backwards compatibility with HTTP/1.0 clients.

Header type	[Request header](https://developer.mozilla.org/en-US/docs/Glossary/Request%20header), [Response header](https://developer.mozilla.org/en-US/docs/Glossary/Response%20header) (response behavior is not specified and is implementation-specific).
[Forbidden request header](https://developer.mozilla.org/en-US/docs/Glossary/Forbidden%20request%20header)	No
[CORS-safelisted response header](https://developer.mozilla.org/en-US/docs/Glossary/CORS-safelisted%20response%20header)	Yes

Syntax

Pragma: no-cache

Directives

• no-cache
  • : Same as Cache-Control: no-cache. Forces caches to submit the request to the origin server for validation before a cached copy is released.

Examples

Pragma: no-cache

Specifications

Browser compatibility

See also

• Cache-Control
• Expires