Title: Website Optimization
Published: June 14, 2024
Last modified: August 20, 2024

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Website Optimization

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# Website Optimization

## Transcript

### Introduction

Numerous research and case studies have shown that the longer a site takes to respond,
the more visitors will abandon it. No matter your site’s focus, providing the best
experience for your visitors is the main goal, so optimizing it for speed is critical.

In this lesson, you will learn what website optimization means, which elements can
impact performance, how to test your site’s speed, and how to improve it.

Web performance pertains to the user experience of load time and runtime. As a practice,
web performance involves measurable factors, such as a page’s loading time and the
time it takes to become interactive, as well as the user’s perception of how long
it took.

### What affects performance

Multiple components determine a site’s speed—software, network conditions, hardware—
each calculated by standard metric. The way to achieve high performance scores is
to optimize each of these moving parts.

Let’s start with software, which covers code and content.

WordPress themes define the pages’ content structure. Some design elements, like
colors, have no effect on performance, whereas others—from fonts and graphic assets
to carousels and popups—could tank your site’s speed.

Selecting newer, more performant file formats is a good practice when dealing with
media and fonts. Images, especially, play a key role in website optimization. We
will thoroughly cover the topic in another lesson dedicated to image optimization
strategies.

While minimizing the number of assets is useful, how they’re loaded is just as important.
From this perspective, a well-coded theme makes all the difference.

#### Themes and plugins

Bloated themes that load too many assets are among the biggest culprits of poor 
performance scores. 

Similarly, the _quality_ of the plugins you use influences how fast your site will
perform, both objectively and perceivably. Plugins that perform excessive requests
to external services, load multiple assets, and constantly perform database queries
will bog down even the best-configured server.

#### Embedded content and third-party elements

Ads, analytics, social media widgets, alternative comments plugins, and externally
hosted assets delay loading, slow down response times, hog bandwidth, and may trigger
higher bounce rates.

Think twice before adding them to your site, and be vigilant about the performance
cost.

### How performance is measured

You can measure performance in two ways: synthetic and real user monitoring (RUM).

Both happen in the browser but synthetic means running tests “in the lab”—under 
predefined conditions and preset variables, while RUM renders findings generated“
in the field”, collecting data from actual site visitors.

In either case, the tests would likely be based on a set of three metrics outlined
by Google and adopted across the industry as “quality signals that are essential
to delivering a great user experience on the web.”

They’re known as _Core Web Vitals_:

 * **Largest Contentful Paint (LCP)** measures when the largest element on the page
   becomes visible.
 * **Cumulative Layout Shift (CLS) **measures how much the elements on the page 
   shift while the page is loading.
 * **Interaction to Next Paint (INP)** a new addition to the list that measures 
   how long it takes for the page to respond to user interactions (clicks, taps,
   and keyboard inputs).

### How to test your site

Testing helps you identify performance bottlenecks. You can do that using various
tools, including [PageSpeed Insights](https://pagespeed.web.dev/) (opens in a new
tab) and [WebPageTest](https://www.webpagetest.org/) (opens in a new tab) .

Maintained by Google, _PageSpeed Insights_ presents synthetic results alongside 
the company’s version of RUM—the Chrome User Experience Report (CrUX). It tests 
the page on mobile and desktop devices and provides suggestions for improvements.

_WebPageTest_ is a more elaborate testing platform. It adds a bunch of helpful features
on top of Google’s metrics, including an environmental impact report, image analysis,
a detailed breakdown of optimization opportunities, and an option to select different
locations, browsers, and connection speeds.

Running WebPageTest for the first time might be daunting, but it’s an invaluable
tool for testing and analyzing your site’s overall performance.

When testing, you’ll encounter other software-driven metrics, including

 * **First Contentful Paint (FCP)**: when the browser displays the first bit of 
   content.
 * **Total Blocking Time (TBT)**: the time elapsed after FCP and before visitors
   can interact with the site.

These are influenced by a combination of loading too many assets and elements and
failing to do so properly.

ℹ️ Performance Lab is a community plugin developed by the WordPress Performance 
Team that might be able to mitigate some of the problems. This plugin combines six
standalone plugins, each designed to tackle a specific performance feature using
the latest browser technology. Once activated, the plugin automatically begins optimizing
your website. There’s no need for manual configuration or adjustments.

### The importance of hosting

The other factors affecting your WordPress site’s speed are network infrastructure,
server hardware, and database operations.

The metric that covers these is the **Time to First Byte (TTFB)**, which measures
the time it takes until the browser receives the first byte. This depends on connection
time—the visitor’s and the server’s.

The faster the connection is established, the faster the bytes are sent, and the
faster your site will load.

Several factors determine the resource delivery speed, including geographical location,
network conditions, hardware configuration, and backend processes. In other words,
hosting matters.

As slow server response times can result from network or hardware issues (CPU, memory,
and storage speed), it’s worth carefully considering every aspect of your hosting
solution—not just the price listed.

### Plugins

Finally, Plugins. Performance plugins won’t be able to reduce CPU load time on the
server or update back-end software, but they can take care of things like CDNs, 
caching, compression, modification, database optimization and sometimes even security.

So even when opting for more affordable shared hosting, it’s a good idea to offset
common challenges with the help of a trusted plugin that lets you use a CDN to minimize
the client’s server round trip times, apply caching to reduce the number of requests,
and enable compression and modification to send the smallest amount of data.

The WordPress Plugin Directory features hundreds of performance and optimization
plugins. Here are a few popular solutions:

 * WP-Optimize
 * W3 Total Cache
 * WP Super Cache
 * Jetpack Boost
 * LiteSpeed Cache

### Conclusion

WordPress contributors have been working hard on improving speed and performance.
Some features are included in Core, but others require users and developers to enable
them.

Make sure you’re using the latest version of WordPress to benefit from the latest
performance-boosting techniques.

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