Page speed is often confused with "site speed," which
is actually the page speed for a sample of page views on a site. Page speed
can be described in either "page load time" (the time it takes to fully
display the content on a specific page) or "time to first byte" (how long it
takes for your browser to receive the first byte of information from the web
You can evaluate your page speed with Google's PageSpeed Insights. PageSpeed
Insights Speed Score incorporates data from CrUX (Chrome User Experience
Report) and reports on two important speed metrics: First Contentful Paint
(FCP) and DOMContentLoaded (DCL).
SEO Best Practices
Google has indicated site speed (and as a result, page
speed) is one of the signals used by its algorithm to rank pages. And
research has shown that Google might be specifically measuring time to first
byte as when it considers page speed. In addition, a slow page speed means
that search engines can crawl fewer pages using their allocated crawl
budget, and this could negatively affect your indexation.
Page speed is also important to user experience. Pages with a longer load
time tend to have higher bounce rates and lower average time on page. Longer
load times have also been shown to negatively affect conversions.
Here are some of the many ways to increase your page speed:
Use Gzip, a software application for file compression,
than 150 bytes.
Do not use gzip on image files. Instead, compress these in a program like
Photoshop where you can retain control over the quality of the image. See
"Optimize images" below.
By optimizing your code (including removing spaces,
commas, and other unnecessary characters), you can dramatically increase
your page speed. Also remove code comments, formatting, and unused code.
Each time a page redirects to another page, your
visitor faces additional time waiting for the HTTP request-response cycle to
complete. For example, if your mobile redirect pattern looks like this:
"example.com -> www.example.com -> m.example.com -> m.example.com/home,"
each of those two additional redirects makes your page load slower.
Browsers have to build a DOM tree by parsing HTML
before they can render a page. If your browser encounters a script during
this process, it has to stop and execute it before it can continue.
Leverage browser caching
Browsers cache a lot of information (stylesheets,
your site, the browser doesn't have to reload the entire page. Use a tool
like YSlow to see if you already have an expiration date set for your cache.
Then set your "expires" header for how long you want that information to be
cached. In many cases, unless your site design changes frequently, a year is
a reasonable time period.
Improve server response time
Your server response time is affected by the amount of
traffic you receive, the resources each page uses, the software your server
uses, and the hosting solution you use. To improve your server response
time, look for performance bottlenecks like slow database queries, slow
routing, or a lack of adequate memory and fix them. The optimal server
response time is under 200ms.
Use a content distribution network
Content distribution networks (CDNs), also called
content delivery networks, are networks of servers that are used to
distribute the load of delivering content. Essentially, copies of your site
are stored at multiple, geographically diverse data centers so that users
have faster and more reliable access to your site.
Be sure that your images are no larger than they need
to be, that they are in the right file format (PNGs are generally better for
graphics with fewer than 16 colors while JPEGs are generally better for
photographs) and that they are compressed for the web.
Use CSS sprites to create a template for images that you use frequently on
your site like buttons and icons. CSS sprites combine your images into one
large image that loads all at once (which means fewer HTTP requests) and
then display only the sections that you want to show. This means that you
are saving load time by not making users wait for multiple images to load.