Pragma
Caches predating Cache-Control need a way to receive no-cache instructions. The Pragma request header is a legacy HTTP/1.0 caching directive retained for this backward compatibility. The specification defines Pragma for requests only, and its behavior in responses was never specified.
Usage
The Pragma header carries the no-cache directive,
which is semantically equivalent to
Cache-Control: no-cache. When a
Cache-Control header is present, the
Pragma value is ignored.
The header originated in HTTP/1.0, which had
no Cache-Control mechanism. HTTP/1.1
introduced Cache-Control as the
replacement, making Pragma obsolete for all
practical purposes. Servers and proxies still include
Pragma as a defense-in-depth measure to ensure
older Caching layers honor the no-cache intent.
The specification defines Pragma solely for backward compatibility. New implementations rely on Cache-Control instead.
CDNs mirror the deprecation in their handling.
CloudFront ignores viewer-sent Pragma entirely
when deciding cache behavior, and Cloudflare's cache
keys carry no Pragma component, so a client sending
Pragma: no-cache rarely changes what an edge
serves. The header's one remaining niche is vendor
debugging: Akamai reads request values like
akamai-x-cache-on and akamai-x-get-cache-key
from Pragma to attach diagnostic response
headers on enabled properties. Browser devtools
"Disable cache" also still sends the header beside
Cache-Control: no-cache, which is why the pair
shows up together in nearly every hard-refresh
request log.
Directives
no-cache
The no-cache directive instructs caches to
revalidate the response with the origin
before serving a stored copy. The behavior matches
Cache-Control: no-cache.
Pragma: no-cache
Example
A request including both Pragma and
Cache-Control to guarantee
compatibility across HTTP/1.0 and
HTTP/1.1 intermediaries. Modern caches use the
Cache-Control value and ignore Pragma.
Cache-Control: no-cache
Pragma: no-cache
A standalone Pragma directive in a request targeting an older proxy server lacking Cache-Control support.
Pragma: no-cache
Crawlers and Pragma
Verified crawler probe
Probe data from verified crawler traffic (September 2026 snapshot) shows which bots send Pragma when requesting pages. Yes marks the header on at least nine of ten sampled requests from the bot, Sometimes marks a smaller share, and No marks absence.
| Crawler | Sends Pragma |
|---|---|
| Amazonbot | No |
| Applebot | No |
| Baiduspider | No |
| Bingbot | Sometimes |
| ClaudeBot | No |
| DuckDuckBot | No |
| GPTBot | No |
| Googlebot | No |
| Googlebot (smartphone) | No |
| Googlebot-Image | No |
| Meta-ExternalAgent | No |
| Meta-WebIndexer | No |
| OAI-SearchBot | No |
| SeznamBot | No |
| YandexBot | No |
| YandexFavicons | No |
