Yelp is one of the largest publishers of crowdsourced reviews about businesses. As of 2021, the company made over a billion dollars in revenue and received close to 150 million visitors each month.
A speed report from Lighthouse paints a rather grim picture and scores Yelp website 11.1 seconds on the speed index (SI), and 41 on Performance.
There are many reasons why the Yelp website is so slow. This includes:
- Bloated JavaScript files
- Unused CSS files
- Render-blocking resources
- Slow server
- Large DOM size
Let’s look at each of these reasons and identify potential ways that Yelp can make its website load faster.
But before we do that, a quick word about our website CWVIQ.com - we are a free email alert service for when websites load slow. We send out notification any time your website is loading very slowly (often due to heavy traffic, or poor scripts). If you have a website, consider setting up an alert so that you can fix issues before they become major. Bloated JavaScript files
Yelp uses a lot of JavaScript to run the website. However, loading them all from one source could slow up the performance of the website. Yelp can avoid this by splitting the code into smaller files. This way, you only load files that are necessary.
The Yelp website can be as much as 1.94 seconds faster by adopting this technique.
Unused CSS files
Yelp uses CSS files to load the styling elements for the website. However, this file contains a lot of unused scripts that can be slowing down page loading by as much as 0.15 seconds. Code splitting may help avoid this issue.
Render-blocking resources
There are scripts on the Yelp website that need to run first before they let the rest of the code be executed. The render-blocking resources issue can shave off around 8.5 seconds from the loading time for the Yelp website.
How do you avoid this? If the script is not critical, avoid having it in the <head> tag of your HTML code. But if you do need to have it there for some reason, make sure to include the defer or async attribute so that they do not block the loading of other resources.
Slow server
According to the Lighthouse report, a slow server may be contributing to nearly 2.67 seconds of additional loading time. In addition to upgrading the server hardware and database systems, Yelp should also look into the server’s application logic to prepare pages faster.
Large DOM size
The Yelp website takes close to 16 seconds to evaluate all the scripts, parse them, compile, and render them. This can be minimized by minimizing the main-thread work.
They may also look at reducing the number of nodes in the DOM. In simpler terms, you need to make sure that the main HTML code is smaller and has fewer nodes. I have explained this in greater detail in this article about DOMContentLoaded.
Anand Srinivasan is the founder of CWVIQ, and has been in the internet media space for over 15 years. He has previously served as the AVP of Products and Head of Business at popular media portals. He has worked with several SaaS and enterprise businesses as an external consultant for their SEO marketing campaigns.