HTTP response header

The number tells the user how many times this version of a page has been served from the cache. A MISS indicates the page was not served from cache. The x-pass-why header will tell the user the reason why the request did not hit the cache.

Header usage statistics

X-Pass-Why response header information and usage statistics.

Websites using header X-Pass-Why 36,014
Percentage of websites that use X-Pass-Why header <0.1%
Total discovered header values 14
Header uses directives No
Header values are unique or random No
Most popular in the country United States of America

Connected technologies

Technologies that utilize the header

WP Engine, category Platform as a Service, total 429,098 websites

Distribution by websites popularity

X-Pass-Why detection in the top websites by popularity

Top 10k sites 13 websites
Top 100k sites 180 websites
Top 1m sites 1,955 websites

Websites utilizing X-Pass-Why

List of websites that use X-Pass-Why header

Domain Country Rank Contacts
my.studiopress.com United States of America 2,931
www.realtor.com United States of America 3,773
www.cardinalpath.com United States of America 4,338
devblogs.microsoft.com United States of America 5,115
www.pagerduty.com United States of America 5,751
www.browserstack.com United States of America 5,813
See full domain list
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Geographical Distribution

Header usage distribution by websites across the globe.

Common header values

List of top common X-Pass-Why header values

Header value Value prevalence
custom-path 45.84%
special path 28.53%
special param 9.09%
pass-path 4.27%
custom-cookie 3.30%
wp-admin 2.93%
logged-in 2.79%
special cookie 2.24%
custom-args 0.62%
pass-cookie 0.28%
auth 0.06%
wpe-cookie 0.04%
nevercache-ua 0.00%
WP non-cached admin 0.00%