X-Pass-Why

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-Why34,164
Percentage of websites that use X-Pass-Why header<0.1%
Total discovered header values12
Header uses directivesNo
Header values are unique or randomNo
Most popular in the country US

X-Pass-Why Directives

X-Pass-Why directives value information and usage statistics

DirectiveShareWebsites countUnique Values

Connected technologies

Technologies that utilize the header

WP Engine, category Web Hosting, total 437,423 websites

Distribution by websites popularity

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

Top 10k sites16 websites
Top 100k sites189 websites
Top 1m sites1,963 websites

Websites utilizing X-Pass-Why

List of websites that use X-Pass-Why header

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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 valueValue prevalence
custom-path43.75%
special path28.90%
special param6.11%
special cookie5.32%
pass-path4.65%
custom-cookie4.19%
logged-in3.18%
wp-admin3.00%
custom-args0.39%
pass-cookie0.26%
auth0.13%
wpe-cookie0.12%