Time To First Byte (TTFB) Shouldn’t Matter. Do This Instead
TTFB Shouldn’t Matter, Test This Instead For Page Speed
Time To First Byte (TTFB) is a metric used to measure how quickly a web server responds to a visitor request. It is used as an industry metric when discussing website speed or page speed and is **the core metric used by popular site speed measurement tools** (Pingdom, PageSpeed Insights, etc). It sounds like it should be an accurate/good measurement for how quickly a page loads for potential visitors, and something webmasters and publishers should be paying close attention to, **but it’s really not**.
In fact, [if you’re concerned about SEO](https://blog.ezoic.com/improve-page-speed-seo-actionable-ways/), visitor experiences, and ad revenue, it really isn’t near as important as measuring a handful of other things.
What you really want to understand is how quickly the visitors are getting the content, how quickly they can interact with the content, and how quickly ads and other important scripts load. [Google Webmasters also give this same advice on site speed](/?p=15161). These are the things that typically affect SEO, UX, and ad revenue the most (relating to speed).
Below, I’ll show you what metrics you should be looking at instead of the arbitrary page speed tools and how you can track those as well. I’ll also tell you why these metrics are more impactful for things like SEO; compared to TTFB which actually isn’t ever a factor in search algorithms.
Google’s top search experts comments on TTFB
> AFAIK we currently don’t use TTFB for anything in search/ranking. It can be a good proxy for user-facing speed, but like other metrics, don’t blindly focus on it.
>
> — John ☆.o(≧▽≦)o.☆ (@JohnMu) [November 30, 2017](https://twitter.com/JohnMu/status/936221054103703553?ref_src=twsrc%5Etfw)
What does testing TTFB measure?
The problem with measuring TTFB
What actually matters to search engines and visitors?
PageSpeed scores are relative to every search query
Practically measuring how fast a website really is…
One of the best ways for publishers to measure and think about delivering content and data quickly is by accounting for DOM (Document Object Model) loading.
**What is DOM?**
> _“Document Object Model (DOM) is a World Wide Web Consortium standard platform and language-neutral interface that allows programs and scripts to dynamically access and update the content, structure, and style of a document.”_
**Why is measuring DOM important for webmasters?**
DOM is a standard object model and programming interface for HTML. It defines:
- The HTML elements as objects
- The properties of all HTML elements
- The methods to access all HTML elements
- The events for all HTML elements
Basically, when the DOM is loaded it is what allows a user to be able to see the page the way it is supposed to be displayed and when all JS and HTML elements are fully-functioning in the session.
**How should DOM be measured?**
There are two types of ways of measuring DOM that matter for all the things we talked about above (SEO, visitor experiences, ad revenue).
- DOM Complete
- DOM Interactive
Why and how to measure DOM instead of TTFB
Testing and measuring DOM
Summarizing the information on TTFB vs. DOM stats
So there it is. We certainly aren’t the only ones talking about how irrelevant TTFB is. Even though Moz did a study on TTFB and its relationships to SEO a while back, they since admitted that any correlation likely has nothing to do with TTFB. Additionally, Cloudflare has talked about how TTFB can actually get worse while actual page speed can actually get better in many cases.
DOM is what the Google webmaster team seems to be spending a lot of time talking about these days, and DOM Complete and DOM Interactive provide a better look at how quickly visitors can access content and when critical page resources are fully-loaded. This better accounts for when you may be optimizing loading based on visitor engagement/SEO; instead of arbitrary loading times.
Questions, concerns, thoughts? Leave them below.