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Magento Defer Parsing JavaScript is an extension provided by BSSCommerce and helps to reduce blocking of page rendering. By Google Pagespeed Test, you will know your site speed and why you need to defer loading of javascript.
Besides, along with Lazy Image Loader, Magento Defer JavaScript Extension is also a useful extension that speeds up Magento store performance by automatically putting JavaScript files to the end of the page after loading all HTML and CSS.
How Magento Defer Parsing JavaScript Extension Works?
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Automatically defer parsing of JavaScript for Magento sites
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Defer Iframes loading
If your webpage has some embed code of other sites, it means that the browser has to load JavaScript files of these pages along with your site. This thing will cause defer score of your website decrease or the site does not perform fast enough for better customer experience. Therefore, using Magento Defer JavaScript will help you to defer these Iframes effectively by loading Iframes of these embed sites only when your site finishes loading completely.
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Improve Magento sites ranking with major search engines
Site speed is also an important factor to influence your website’s ranking on Search Engine Result Pages. Therefore, with Magento Defer JavaScript extension, your site speed is improved and search engines will evaluate it more highly than other ones with slower speed.
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Dramatically improve execution and rendering time which helps engage more customers
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Fix all the problems with Full Page Cache module and it works perfectly with FPC module.
Why is Magento Defer JavaScript Extension your must-have extension?
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Effective Magento site speed improvement
The fact that scripts must be downloaded, parsed, and executed before the browser can begin to render a web page causes much of delay in time to load the main page at the startup. That ugly truth can make your customers leave your site at their first visit as many studies have shown that users will not tolerate more than a 4 second load time.
Magento Defer Parsing of JavaScript is developed to solve out this issue. It allows optimizing your Magento store performance quickly and easily.
The below picture shows Page Speed Result of http://demo.bsscommerce.com/productpage/index.php before installing Magento Defer JavaScript Extension.
And look at how it changes after Magento Defer JavaScript Extension by BSSCommerce is installed.
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Defer parsing JavaScript for Magento until the last moment
Basically, Deferring means that the other HTML files and CSS is loaded first then parsing of JavaScript files is implemented after all. This has no effect on the performance or usability of your web page, it merely rearranges the loading process so that JavaScript is deferred until the last possible moment - the outcome of this process is that your Magento page appears much quicker after defer parsing of JavaScript.
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Easy configuration from backend
With a few clicks, you can get this extension work on your online store for better speed performance. Magento Defer JavaScript Extension by BSSCommerce is developed by our certificated developers who ensure that it’s well-compatible with default Magento and hardly find any conflicts.
User Guide
Below is the guide which tells you how our Defer Pasing Javascript works in Magento.
Click here to check out BSSCommerce's best extensions for your Magento store. We will help you to boost both your website's performance and sales.
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Reviews
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Amazing ExtensionWell, this extension is awesome! My website works fast now, and google pagespeed is 97. It is working out of the box, no issues found yet. Our store was fast and stable even during black friday and christmas sales when traffic was is very high.
Highly recommend!verified buyer
Reviewed by Ginger A. Devine on 27 February 2018 -
Best SolutionThis extension working perfectly on Magento CE1.5
verified buyer
Reviewed by Onur on 15 January 2018 -
Does as advertisedMy speed loaded way faster and browsing seems snappier especially on mobile. Worth the price
verified buyer
Reviewed by Phu trinh on 06 October 2017 -
Best Defer JavaScript for Magento sitesThank to Defer Javascript extension, I can slove slow speed problem of my website.
It was so slow and made customers to leave site immediately.
I choose your extension because it is simple but effective quickly. and so amazing it improve my site so much.
Love it!verified buyer
Reviewed by Mandel Marleau on 30 May 2017 -
DeveloperDeferring js and css is important so that your pages' content is toward the top of your page. Reason: Search Engine crawlers like Googlebot and Bingbot can get to a page's readable content without having to parse through lines and lines of scripts and style sheets.
BSS Defer Javascript does exactly that. And it does it well, a.k.a eloquently.verified buyer
Reviewed by David Radovanovic on 17 December 2016 -
Does exactly what it claimsDoes exactly what it claims. HTML compression broke site, though easily reversed. Suggestion: would be nice if large blocks of white (previous location of scripts) in source code was somehow removed. Other than that, I would highly recommend. Thanks!
verified buyer
Reviewed by David Radovanovic on 13 December 2016 -
great extensionit works great!! very good job BSS!!
verified buyer
Reviewed by targetsas on 10 October 2016 -
Very good extension and great support!This module helped me a lot for my Google Page Speed score. Defering Js is essential and this module handeled it just fine. I had some problems after installing, as the compatability with the Lesti FPC was not 100%. However, the senior and founder of the bizz helped me and came up with a solution very swiftly. I highly recommend anyone to use this module. Thnx Trung!
From Magento Connect on May 11, 2015verified buyer
Reviewed by wjohan on 07 March 2016 -
Great extension to improve Magento speed"This extension fixed my Defer JavaScript issue of my Magento store.
I faced few problem after install but their support helped me to resolve those issues. Great support!"
From Magento Connect on June 26, 2015verified buyer
Reviewed by bdsabur on 07 March 2016 -
Great product"Great product by a great company!
Does exactly what you want!"
From Magento Connect on June 26, 2015verified buyer
Reviewed by jmnscj on 07 March 2016 -
Good extension, even better support!Thanks to BSSCommerce we can get our GTMetrix / Google Pagespeed rating to a higher level. Support is superb, although they need to do some tweaking in extension files.
From Magento Connect on August 20, 2015verified buyer
Reviewed by gjr on 07 March 2016 -
Awsome Support / Extension"This worked great to take our site from 0/100 to 100/100 in Yslow and Gmetrix. BSS helped resolve the installation with great enthusiasm"
From Magento Connect on September 24, 2015verified buyer
Reviewed by Weedwaka on 07 March 2016 -
Does exactly what its supposed to!"I had this extension installed in our store. Basically based on the information from GTMetrix, that our site speed can be faster if using Defer Javascript. Bsscommerce installed the extension for me at no additional cost, went really fast and smooth and does exactly what its supposed to. Rating on GTMetrix has improved and also the actuall speed is faster after carefully monitoring the difference!
I would also recommend letting Bsscommerce help with the installation, as I know that defer javascript can be a bit tricky.
Thank you very much for a great extension and awesome support!"
From Magento Connect on January 8, 2016verified buyer
Reviewed by 2xa-dreas on 07 March 2016 -
A must for all Magento website"As most of us I needed a way to speed up my magento website.
Being on a shared hosting the scenario was pretty scared, but after a mail with the developer I follow his suggestion and installed both the defer js and the bss FPC.
The results are amazing!
I went from 11 sec. to 4 sec. ( using gtmetrix) on my Magento 1.9.0.1 website.
I had few minor issues related to custom template but the developer help me in no time.
Strongly suggested both for the support and for the funtionality."
From Magento Connect on January 27, 2016verified buyer
Reviewed by gtatarella on 07 March 2016 -
Best way to defer parsing of javascript in Magento!"After speeding up our website through the help of GTMetrix the only thing left was the message to 'defer parsing of javascript'. We looked through tutorials to do it ourselfs but without success. After searching for a while I came across this extension and decided to give it a try. It worked out of the box, even though some strange things were happening that later on could be addressed to a totally different change we made. The support team helped us find the problem even though it had nothing to do with their extension so we know they give great support as well!"
From Magento Connect on February 5, 2016verified buyer
Reviewed by lostoestel on 07 March 2016 -
Great extension"This extension sorted out our defer javascript problems we had when testing with webmaster tools and the likes.
0 problems and worked right away."
From Magento Connect on February 5, 2016verified buyer
Reviewed by mikepedersen on 07 March 2016 -
Simple the best"We have been searching a solution for the defer javascript on internet like anything. Defer Parsing was the main issue in the overall speed of our website but our search came to an end when we see this extension. We immediately contact the support and support was so helpful in helping us decide to buy this extension.
Overall, a very pleasant experience."
From Magento Connect on February 5, 2016verified buyer
Reviewed by AbhishekHFN on 07 March 2016 -
GoodGreat extension!
verified buyer
Reviewed by Randles on 22 January 2016 -
Best support, extension, everythingAn amazing module, my total sales increases sharply! Thank you very much for this helpful support and unbelievable innovation! Good luck!
verified buyer
Reviewed by Brandon on 04 January 2016 -
Awsome!I have been absent for some time, but now I remember why I used to love this website. Thanks, I'll try and check back more often.
verified buyer
Reviewed by Adam on 19 November 2015 -
It's so great to see your site is working on smoothy"I was very impressed on how Defer Javascript can improve my site speed.
It's so great to see my site is working on smoothy. Highly recommend!"verified buyer
Reviewed by Leoknz on 06 August 2015 -
Satisfied with the quality and priceI was trying to find a solution to the magento cache for a long time, tried modules for varnish and for memcached
and I still had no best answer for speed loading solution until finding out Defer JavaScript. It works very well as described and I am satisfied with the price.verified buyer
Reviewed by Richardsz on 09 June 2015 -
Satisfied with the quality and price"I was trying to find a solution to the magento cache for a long time, tried modules for varnish and for memcached
and I still had no best answer for speed loading solution until finding out Defer JavaScript. It works very well as described and I am satisfied with the price."verified buyer
Reviewed by Richardsz on 03 April 2015 -
Clean code and many features"I've tried many combinations to improve Magento performance, this module beats all.
Clean code, many features and good support!"verified buyer
Reviewed by Hanzy on 25 March 2015 -
I'm waiting for BSS new modulesI bought 3 extensions from BSS. I always received very reasonable price with the best support ever. They also update new solutions for online store. I'm waiting for your new modules
verified buyer
Reviewed by Jessica on 23 March 2015 -
WalterI have to say that Defer JavaScript is better than other more expensive solutions.
I'm amazed at how it works and returns it brings back. Very useful extension!verified buyer
Reviewed by Awesome extension! on 12 March 2015