epresentation ](https://www.rfc-
editor.org/rfc/rfc9110#section-6.4) of the target resource.

A client can request that a server emit a ` Content-Digest ` by issuing [ `
Want-Content-Digest ` ](/en-US/docs/Web/HTTP/Headers/Want-Content-Digest) .

Header type  |  [ Representation header ](/en-US/docs/Glossary/Representation_header)  
---|---  
[ Forbidden header name ](/en-US/docs/Glossary/Forbidden_header_name) |  no   
  
##  Syntax

` Content-Digest ` describes an [ RFC8941 dictionary ](https://www.rfc-
editor.org/rfc/rfc8941#section-3.2) with its keys being names of digest
algorithms and its values being the digest in bytes (or an integer digest for
legacy digest algorithms).

**Note:** In contrast to earlier drafts of the specification, the standard-
base64-encoded digest bytes are wrapped in colons ( ` : ` , ASCII 0x3A) as
part of the [ dictionary syntax ](https://www.rfc-editor.org/rfc/rfc8941#name-
byte-sequences) .

http

    
    
    Content-Digest: <digest-algorithm>=:<standard-padded-base64-digest-value>:, ...
    Content-Digest: <digest-algorithm-integer-checksum>=<integer-checksum-value>, ...
    

##  Directives

For permissible digest algorithms see [ ` Repr-Digest ` ](/en-
US/docs/Web/HTTP/Headers/Repr-Digest) .

##  Examples

    
    
    Content-Digest: unixcksum=916142062
    Content-Digest: md5=:+thA//8pGVGk2VYuJkFNvA==:, unixsum=26869
    

##  Specifications

Specification  
---  
[ Unknown specification  
](https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-digest-headers-12)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ ` Repr-Digest ` ](/en-US/docs/Web/HTTP/Headers/Repr-Digest) , [ ` Want-Content-Digest ` ](/en-US/docs/Web/HTTP/Headers/Want-Content-Digest) , [ ` Want-Repr-Digest ` ](/en-US/docs/Web/HTTP/Headers/Want-Repr-Digest)
  * [ ` ETag ` ](/en-US/docs/Web/HTTP/Headers/ETag)

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