Total blocking time (TBT).

A website that loads as fast as possible: this is the wish of every business owner. Measuring Total Blocking Time is one way to gain more insight into this. What is Total Blocking Time and how does it work on a Web site? You can read all the important information on this page.

What is Total Blocking Time?

Total Blocking Time (TBT) is a measurement of how long a page loads. It measures how long a page’s block takes to load. When there is blocking, it takes longer for a visitor to have options on a website.

This is how TBT works

Total Blocking Time is part of Google Lighthouse; it is one of the Google Core Web Vitals. The loading time of a Web site is one of the most important components of a properly functioning site. The faster a page loads, the better. A slow website may cause visitors to leave your website and therefore not proceed to make a purchase.

Knowing about important things like Total Blocking Time will give you a better understanding of the current status of your website and how to change it. TBT measures what is going on on the website between the First Contentful Paint and the Time to Interactive, so to speak.

Total Blocking Time _ Glossary of terms

The impact of Total Blocking Time on SEO.

Total Blocking Time potentially impacts the SEO of a website or page, especially when you consider other important issues, such as Largest Contentful Paint and Cumulative Layout Shift. The latter two are important ranking factors for Google, so it is smart to include them in the SEO strategy.

My advice

Google Lighthouse’s key measurement tools offer great insight and opportunities for a website’s search engine optimization, as well as its usability.

We recommend delving into this metric from Google, in conjunction with other key metrics. This gives you insight into the speed of your page, but also makes it a lot easier to make changes. This makes for a faster website, more traffic and also more conversion.

Senior SEO-specialist

Ralf van Veen

Senior SEO-specialist
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I have been working for 10 years as an independent SEO specialist for companies (in the Netherlands and abroad) that want to rank higher in Google in a sustainable manner. During this period I have consulted A-brands, set up large-scale international SEO campaigns and coached global development teams in the field of search engine optimization.

With this broad experience within SEO, I have developed the SEO course and helped hundreds of companies with improved findability in Google in a sustainable and transparent way. For this you can consult my portfolio, references and collaborations.

This article was originally published on 17 October 2023. The last update of this article was on 17 January 2024. The content of this page was written and approved by Ralf van Veen. Learn more about the creation of my articles in my editorial guidelines.