Title: is browser caching working?
Last modified: August 26, 2019

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# is browser caching working?

 *  Resolved [Megunticook](https://wordpress.org/support/users/megunticook/)
 * (@megunticook)
 * [6 years, 8 months ago](https://wordpress.org/support/topic/is-browser-caching-working/)
 * I’ve been using W3TC for about a month and a half now, testing at GT Metrix and
   tweaking the plugin to get the best results.
 * One thing I’m confused about is that GT Metrix keeps giving me a big fat zero
   for browser caching–the report says “expiration not specified.” But when I check
   a specific file in the Network tab of Chrome Developer Tools, I can see both “
   cache-control: max-age=2592000” and “expires: access plus 30 days” in the response
   headers. Also seeing a 304 code, which means my browser is successfully caching
   the file, right?
 * Is this just a bug in GT Metrix? Or do I have something misconfigured? How do
   I ensure visitors to site are caching these files?
 * Thanks. I’ll paste the full header info. for one image file in case that’s helpful:
 * Request URL: [https://cdn.swansislandcompany.com/wp-content/uploads/2017/07/rare-wool-throw-335×335.jpg](https://cdn.swansislandcompany.com/wp-content/uploads/2017/07/rare-wool-throw-335×335.jpg)
   
   Request Method: GET Status Code: 304 Remote Address: [2600:9000:21da:f600:0:dc04:
   fa40:93a1]:443 Referrer Policy: no-referrer-when-downgrade age: 44072 cache-control:
   max-age=2592000 date: Mon, 26 Aug 2019 11:25:00 GMT etag: “afa710313270f917f718009b10ec85e1″
   expires: access plus 30 days server: AmazonS3 status: 304 via: 1.1 6cf3377e93378c7e591abeecafea2e6a.
   cloudfront.net (CloudFront) x-amz-cf-id: zsng5b1ZflBB45PBpqy7CZ58onZ26ukBT7fAD33_9deOenEykRAA9w
   == x-amz-cf-pop: EWR53-C1 x-amz-meta-access-control-allow-origin: * x-amz-meta-
   content-type: image/jpeg x-amz-meta-last-modified: Tue, 13 Aug 2019 10:27:53 
   GMT x-amz-meta-link: <[https://swansislandcompany.com/usr/share/nginx/html/wp-content/uploads/2017/07/rare-wool-throw-335×335.jpg&gt](https://swansislandcompany.com/usr/share/nginx/html/wp-content/uploads/2017/07/rare-wool-throw-335×335.jpg&gt);;
   rel=”canonical” x-cache: Hit from cloudfront :authority: cdn.swansislandcompany.
   com :method: GET :path: /wp-content/uploads/2017/07/rare-wool-throw-335×335.jpg:
   scheme: https accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/
   webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3 accept-encoding: gzip,
   deflate, br accept-language: en-US,en;q=0.9 cache-control: max-age=0 cookie: 
   _ga=GA1.2.395516380.1534482950; _gid=GA1.2.1254501317.1566779581 if-modified-
   since: Mon, 19 Aug 2019 12:40:54 GMT if-none-match: “afa710313270f917f718009b10ec85e1”
   sec-fetch-mode: navigate sec-fetch-site: none sec-fetch-user: ?1 upgrade-insecure-
   requests: 1 user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/
   537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fis-browser-caching-working%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Contributor [Marko Vasiljevic](https://wordpress.org/support/users/vmarko/)
 * (@vmarko)
 * [6 years, 8 months ago](https://wordpress.org/support/topic/is-browser-caching-working/#post-11867433)
 * Hello [@megunticook](https://wordpress.org/support/users/megunticook/),
 * I am sorry you are having issues with Browser Cache settings but I am happy to
   assist you.
    In your GTmetrix report, when you hover over “What’s this mean?”
   under Leverage browser caching, you’ll see the following: “General guidelines
   for setting expiries: Truly static content (global CSS styles, logos, etc.) –
   access plus 1 year Everything else – access plus 1 week”. In your case, expiration
   is set to 30 days, which is not enough, static files like CSS&jpg should be 1
   year. I hope this helps.
 *  Thread Starter [Megunticook](https://wordpress.org/support/users/megunticook/)
 * (@megunticook)
 * [6 years, 8 months ago](https://wordpress.org/support/topic/is-browser-caching-working/#post-11868052)
 * OK–but why is GT Metrix flagging my image files also, which are set to 30 days?
   The example I gave above was from one of the many files GT Metrix listed in their
   report as “expiration not specified”
 * I’ll try changing the expiration on CSS, logo file, etc. to access plus 1 year.
 * But can I safely assume that GTMetrix is mistaken about all those images and 
   other files? Or do I have something misconfigured?
 * Thanks.
 *  Plugin Contributor [Marko Vasiljevic](https://wordpress.org/support/users/vmarko/)
 * (@vmarko)
 * [6 years, 8 months ago](https://wordpress.org/support/topic/is-browser-caching-working/#post-11868355)
 * Hello [@megunticook](https://wordpress.org/support/users/megunticook/),
 * The default Expires header lifetime: value in Performance>Browser Cache>Media&
   Other Files is 31536000s
    Images are also a static content which as per GtMetrix
   should be access plus 1 year

Viewing 3 replies - 1 through 3 (of 3 total)

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## Tags

 * [browser cache](https://wordpress.org/support/topic-tag/browser-cache/)
 * [expiration](https://wordpress.org/support/topic-tag/expiration/)

 * 3 replies
 * 2 participants
 * Last reply from: [Marko Vasiljevic](https://wordpress.org/support/users/vmarko/)
 * Last activity: [6 years, 8 months ago](https://wordpress.org/support/topic/is-browser-caching-working/#post-11868355)
 * Status: resolved