Are Third-Party Codes Slowing Down Your Site?

site speed

I’m here to tell you that the answer is probably “yes.” However, this can easily be altered with a little bit of testing and change of code.

Keep on reading to find out how you can discover what resources are slowing down your website’s load time.

Step 1: Run a Speed Test

Google’s developers have created this free test that will analyze URLs on your website and grade them out of 100 on how fast they load in both a mobile and desktop environment.

When the test is complete, scroll down to “Diagnostics.” If you have any third-party code on your site impacting your speed, you will see it below. In this example, you can see the results from running a test on

speed diagnostics

Step 2: Analyze Results

As you can see, Twitter has its own code, alongside Google Analytics and Branch Metrics running on the site. Your own tests will likely see some important code like analytics on your site with others such as Google Tag Manager, Google Ads, Facebook Pixel, any CRM integrations, and chatbot platforms.

You will want to pay attention to the “Main-Thread Blocking Time” column as this is a direct correlation to how the platform is interfering with load time. As you can see above, it seems Twitter’s own code is hurting this site the most with a whopping 1,292ms!

And if you see any results of platforms you do not recognize, be sure to ask your developer what they are being using for. This will help you determine if there are any that can be eliminated.

Step 3: Remove Code

If you are familiar with coding at all, or know how to access the header and footer areas of your website, you can likely remove the code yourself safely. Otherwise, kindly ask your web developer to do it for you. Just be sure to take backups!

Step 4: Re-test

Once the code has been removed from your website, go ahead and re-test your site using the same tool as in step 1 and see if anything has improved!

With our own testing, a major source’s code had a main-thread blocking time of 620ms, and there was a score differential of 25 points in mobile when tested on and then removed from the site.

Learn More About Website Speed and Marketing

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Sarah Blocksidge

About the Author

Sarah Blocksidge

Sarah is the Marketing Director at Sixth City Marketing and has been with the company since 2016. Her main role is to attract more B2B clients for the company. Over the years, she has been mentioned on HubSpot, Content Marketing Institute, Fast Company, Mashable, and many other notable sites.

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