Title: First Byte Time
Last modified: November 9, 2018

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# First Byte Time

 *  Resolved [serpevil](https://wordpress.org/support/users/serpevil/)
 * (@serpevil)
 * [7 years, 7 months ago](https://wordpress.org/support/topic/first-byte-time-2/)
 * Hi
 * Thx to autoptimize i reached 100/100 score on pagespeed but First Byte Time is
   horrible.
 * First Byte Time is getting fixed after i disable autoptimize thats why i am sure
   the plugin is causing this. I saw this was a known issue but wasnt fixed on 2.4.1
   as promised. Will be there a new update trying to fix that or i have to delete
   the plugin ?
 * Thank you

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

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [7 years, 7 months ago](https://wordpress.org/support/topic/first-byte-time-2/#post-10864654)
 * first of all; do make sure you’re using a page caching plugin (which AO is not),
   because AO will _always_ add _some_ time for the TTFB without a page cache in
   play.
 * next; the known issue is most certainly fixed (slowdown due to multibyte-character
   support, which is now disabled by default).
 * other then that; so when playing with the settings, have you tried doing only
   CSS or only JS optimization to see which one is causing the delay? have you tried
   different settings (e.g. turning the “also optimize inline”-options off) to see
   if that makes a difference? have you tried excluding some of the CSS or JS (depending
   on the answer to the first question) to see if that makes a difference?
 * we’ll get there! 🙂
    frank
 *  Thread Starter [serpevil](https://wordpress.org/support/users/serpevil/)
 * (@serpevil)
 * [7 years, 7 months ago](https://wordpress.org/support/topic/first-byte-time-2/#post-10866100)
 * Hi and thx for the answer, a cache plugin solved my first byte issue however 
   when setting CDN (cdn.mydomain.com) into the plugin the only thing delivered 
   via CDN is cache/autoptimize/css/autoptimize_8cdd6103eeb77fd3115a87fd2b67f30e.
   css and not any image or anything else. Should i integrate CDN using a different
   plugin ?
 * Thank you
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [7 years, 7 months ago](https://wordpress.org/support/topic/first-byte-time-2/#post-10866117)
 * yes, AO only CDN’s the JS, CSS and background images in CSS, so if you want other
   resources to be CDN’ed you’ll need to use another plugin (some page caches have
   that ability, e.g. WP Super Cache).
 * hope this helps,
    frank

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

The topic ‘First Byte Time’ is closed to new replies.

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 * 3 replies
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [7 years, 7 months ago](https://wordpress.org/support/topic/first-byte-time-2/#post-10866117)
 * Status: resolved