Autoptimize speeds up your website by optimizing JS, CSS, images (incl. lazy-load), HTML and Google…
If you consider performance important, you really should use one of the many caching plugins to do page caching. Some good candidates to complement Autoptimize that way are e.g. WP Super Cache, HyperCache, Comet Cache or KeyCDN’s Cache Enabler.
We provide great Autoptimize Pro Support and Web Performance Optimization services, check out our offering on https://autoptimize.com/!
(Speed-surfing image under creative commons by LL Twistiti)
Just install from your WordPress “Plugins > Add New” screen and all will be well. Manual installation is very straightforward as well:
It concatenates all scripts and styles, minifies and compresses them, adds expires headers, caches them, and moves styles to the page head, and scripts (optionally) to the footer. It also minifies the HTML code itself, making your page really lightweight.
HTTP/2 is a great step forward for sure, reducing the impact of multiple requests from the same server significantly by using the same connection to perform several concurrent requests. That being said, concatenation of CSS/ JS can still make a lot of sense, as described in this css-tricks.com article and this blogpost from one of the Ebay engineers. The conclusion; configure, test, reconfigure, retest, tweak and look what works best in your context. Maybe it’s just HTTP/2, maybe it’s HTTP/2 + aggregation and minification, maybe it’s HTTP/2 + minification (which AO can do as well, simply untick the “aggregate JS-files” and/ or “aggregate CSS-files” options). And Autoptimize can do a lot more then “just” optimizing your JS & CSS off course 😉
Although Autoptimize comes without any warranties, it will in general work flawlessly if you configure it correctly. See “Troubleshooting” below for info on how to configure in case of problems.
Starting from AO 2.1 WordPress core’s jquery.js is not optimized for the simple reason a lot of popular plugins inject inline JS that is not aggregated either (due to possible cache size issues with unique code in inline JS) which relies on jquery being available, so excluding jquery.js ensures that most sites will work out of the box. If you want optimize jquery as well, you can remove it from the JS optimization exclusion-list (you might have to enable “also aggregate inline JS” as well or switch to “force JS in head”).
If not “forced in head”, Autoptimized JS is not render blocking as it has the “defer” flag added. It is however possible another plugin removes the “defer”-flag. Speed Booster Pack was reported doing this, but the behavior has not been confirmed yet.
With the default Autoptimize configuration the CSS is linked in the head, which is a safe default but has Google PageSpeed Insights complaining. You can look into “inline all CSS” (easy) or “inline and defer CSS” (better) which are explained in this FAQ as well.
CSS in general should go in the head of the document. Recently a.o. Google started promoting deferring non-essential CSS, while inlining those styles needed to build the page above the fold. This is especially important to render pages as quickly as possible on mobile devices. As from Autoptimize 1.9.0 this is easy; select “inline and defer CSS”, paste the block of “above the fold CSS” in the input field (text area) and you’re good to go!
There’s no easy solution for that as “above the fold” depends on where the fold is, which in turn depends on screensize. There are some tools available however, which try to identify just what is “above the fold”. This list of tools is a great starting point. The Sitelocity critical CSS generator and Jonas Ohlsson’s criticalpathcssgenerator are nice basic solutions and http://criticalcss.com/ is a premium solution by the same Jonas Ohlsson. Alternatively this bookmarklet (Chrome-only) can be helpful as well.
The short answer: probably not. Although inlining all CSS will make the CSS non-render blocking, it will result in your base HTML-page getting significantly bigger thus requiring more “roundtrip times”. Moreover when considering multiple pages being requested in a browsing session the inline CSS is sent over each time, whereas when not inlined it would be served from cache.
Autoptimize does not have its proper cache purging mechanism, as this could remove optimized CSS/JS which is still referred to in other caches, which would break your site. Moreover a fast growing cache is an indication of other problems you should avoid.
Instead you can keep the cache size at an acceptable level by either:
Despite above objections, there are 3rd party solutions to automatically purge the AO cache, e.g. using this code or this plugin, but for reasons above these are to be used only if you really know what you’re doing.
When clicking the “Delete Cache” link in the Autoptimize dropdown in the admin toolbar, you might to get a “Your cache might not have been purged successfully”. In that case go to Autoptimizes setting page and click the “Save changes & clear cache”-button.
Moreover don’t worry if your cache never is down to 0 files/ 0KB, as Autoptimize (as from version 2.2) will automatically preload the cache immediately after it has been cleared to speed further minification significantly up.
When clearing AO’s cache, no page cache should contain pages (HTML) that refers to the removed optimized CSS/ JS. Although for that purpose there is integretion between Autoptimize and some page caches, this integration does not cover 100% of setups so you might need to purge your page cache manually.
At the moment (June 2017) it seems RocketLoader might break AO’s “inline & defer CSS”, which is based on Filamentgroup’s loadCSS, resulting in the deferred CSS not loading.
Autoptimize is not a simple “fix my Pagespeed-problems” plugin; it “only” aggregates & minifies (local) JS & CSS and images and allows for some nice extra’s as removing Google Fonts and deferring the loading of the CSS. As such Autoptimize will allow you to improve your performance (load time measured in seconds) and will probably also help you tackle some specific Pagespeed warnings. If you want to improve further, you will probably also have to look into e.g. page caching and your webserver configuration, which will improve real performance (again, load time as measured by e.g. https://webpagetest.org) and your “performance best practise” pagespeed ratings.
A whole lot; there are filters you can use to conditionally disable Autoptimize per request, to change the CSS- and JS-excludes, to change the limit for CSS background-images to be inlined in the CSS, to define what JS-files are moved behind the aggregated one, to change the defer-attribute on the aggregated JS script-tag, … There are examples for some filters in autoptimize_helper.php_example and in this FAQ.
Starting from version 1.7.0, CDN is activated upon entering the CDN blog root directory (e.g. http://cdn.example.net/wordpress/). If that URL is present, it will used for all Autoptimize-generated files (i.e. aggregated CSS and JS), including background-images in the CSS (when not using data-uri’s).
If you want your uploaded images to be on the CDN as well, you can change the upload_url_path in your WordPress configuration (/wp-admin/options.php) to the target CDN upload directory (e.g. http://cdn.example.net/wordpress/wp-content/uploads/). Do take into consideration this only works for images uploaded from that point onwards, not for images that already were uploaded. Thanks to BeautyPirate for the tip!
Autoptimize supports this, but it is not enabled by default because non-local fonts might require some extra configuration. But if you have your cross-origin request policy in order, you can tell Autoptimize to put your fonts on the CDN by hooking into the API, setting
true this way;
Nothing, when on Cloudflare your autoptimized CSS/ JS is on the Cloudflare’s CDN automatically.
If your webserver is properly configured to handle compression (gzip or deflate) and cache expiry (expires and cache-control with sufficient cacheability), you don’t need Autoptimize to handle that for you. In that case you can check the “Save aggregated script/css as static files?”-option, which will force Autoptimize to save the aggregated files as .css and .js-files (meaning no PHP is needed to serve these files). This setting is default as of Autoptimize 1.8.
Both CSS and JS optimization can skip code from being aggregated and minimized by adding “identifiers” to the comma-separated exclusion list. The exact identifier string to use can be determined this way:
<script>funky_data='Won\'t you take me to, Funky Town'</script>, the identifier is “funky_data”.
If your blog doesn’t function normally after having turned on Autoptimize, here are some pointers to identify & solve such issues using “advanced settings”:
AO minifies excluded JS/ CSS if the filename indicates the file is not minified yet. As of AO 2.5 you can disable this on the “JS, CSS & HTML”-tab under misc. options by unticking “minify excluded files”.
Make sure you’re not running other HTML, CSS or JS minification plugins (BWP minify, WP minify, …) simultaneously with Autoptimize or disable that functionality your page caching plugin (W3 Total Cache, WP Fastest Cache, …). Try enabling only CSS or only JS optimization to see which one causes the server error and follow the generic troubleshooting steps to find a workaround.
If you are running Apache, the htaccess file written by Autoptimize can in some cases conflict with the AllowOverrides settings of your Apache configuration (as is the case with the default configuration of some Ubuntu installations), which results in “internal server errors” on the autoptimize CSS- and JS-files. This can be solved by setting AllowOverrides to All.
Domain mapped multisites require Autoptimize to be initialized at a different WordPress action, add this line of code to your wp-config.php to make it so to hook into
setup_theme for example:
define( 'AUTOPTIMIZE_SETUP_INITHOOK', 'setup_theme' );
Autoptimize does a number of checks before actually optimizing. When one of the following is true, your pages won’t be optimized:
<xsl:stylesheetin the response (indicating the output is not HTML but XML)
<html ampin the response (as AMP-pages are optimized already)
Disable the option to have Autoptimize active for logged on users and go crazy dragging and dropping 😉
Disable the option to optimize cart/ checkout pages (works for WooCommerce, Easy Digital Downloads and WP eCommerce).
js/jquery/jquery.js is in the comma-separated list of JS optimization exclusions (this is excluded in the default configuration).
js/jquery/jquery.js to the comma-separated list of JS optimization exclusions.
add_filter( 'run_ngg_resource_manager', '__return_false' ); or you can tell Autoptimize to initialize earlier, by adding this to your wp-config.php:
Starting with version 1.6.6 Autoptimize excludes everything inside noptimize tags, e.g.:
<!--noptimize--><script>alert(‘this will not get autoptimized’);</script><!--/noptimize-->
You can do this in your page/ post content, in widgets and in your theme files (consider creating a child theme to avoid your work being overwritten by theme updates).
Yes, if you want to serve files from e.g. /wp-content/resources/aggregated_12345.css instead of the default /wp-content/cache/autoptimize/autoptimize_12345.css, then add this to wp-config.php:
Yes, but this is off by default. You can enable this by passing ´true´ to ´autoptimize_filter_cache_create_static_gzip´. You’ll obviously still have to configure your webserver to use these files instead of the non-gzipped ones to avoid the overhead of on-the-fly compression.
This new option in Autoptimize 2.3 removes the inline CSS, inline JS and linked JS-file added by WordPress core. As such is can have a small positive impact on your site’s performance.
Although some online performance assessement tools will single out “query strings for static files” as an issue for performance, in general the impact of these is almost non-existant. As such Autoptimize, since version 2.3, allows you to have the query string (or more precisely the “ver”-parameter) removed, but ticking “remove query strings from static resources” will have little or no impact of on your site’s performance as measured in (milli-)seconds.
Preconnect is a somewhat advanced feature to instruct browsers (if they support it) to make a connection to specific domains even if the connection is not immediately needed. This can be used e.g. to lessen the impact of 3rd party resources on HTTPS (as DNS-request, TCP-connection and SSL/TLS negotiation are executed early). Use with care, as preconnecting to too many domains can be counter-productive.
When image optimization is on, Autoptimize will look for png, gif, jpeg (.jpg) files in image tags and in your CSS files that are loaded from your own domain and change the src (source) to the ShortPixel CDN for those. Important: this can only work for publicly available images, otherwise the image optimization proxy will not be able to get the image to optimize it, so firewalls or proxies or password protection or even hotlinking-prevention might break image optimization.
No; Image optimization depends on the ability of the external image optimization service to fetch the original image from your site, optimize it and save it on the CDN. If you images cannot be downloaded by anonymous visitors (due to firewall/ proxy/ password protection/ hotlinking-protection), image optimization will not work.
Have a look at Shortpixel’s FAQ.
As from AO 2.4 AO “listens” to page cache purges to clear its own cache. You can disable this behavior with this filter;
Main reason (apart from occasional hickups that seem to be inherent to plugin upgrades) is that AO 2.4 requires you to be running PHP 5.3 or higher. And let’s face it; you should actually be running PHP 7.x if you value performance (and security and support), no?
By default AO uses non multibyte-safe string methods, but if your PHP has the mbstring extension you can enable multibyte-safe string functions with this filter;
You can get help on the wordpress.org support forum. If you are 100% sure this your problem cannot be solved using Autoptimize configuration and that you in fact discovered a bug in the code, you can create an issue on GitHub. If you’re looking for premium support, check out our Autoptimize Pro Support and Web Performance Optimization services.
Just fork Autoptimize on Github and code away!
autoptimize_filter_js_minify_excluded-filter to ensure backwards-compatibility and thus avoid breaking Smart Cookie Kit which expected that 3rd parameter.
display=swapto Autoptimized (CSS-based) Google Fonts.
wp-content/uploadsfrom CSS optimization (Divi, Avada & possibly others store page-specific CSS there)
autoptimize_filter_toolbar_showfilter to disable), a big thanks to Pablo Custo for his hard work on this nice feature!
autoptimize_filter_cachecheck_sendmailfilter to disable or pass alternative email to the
autoptimize_filter_cachecheck_mailtofilter to change email-address)
autoptimize_filter_cache_create_static_gzip, kudo’s to (Draikin)[https://github.com/Draikin] for this!
data-noptimizeattribute will be excluded from optimization