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A 0.1 second improvement in 4-speed metrics can improve progression rates across the purchase funnel.

A new study Milliseconds make millions
reveals the significant impact of mobile site speed on consumers' willingness to spend money and engage with brands online. The results show that even a 0.1 second improvement in loading times can improve progression rates across the entire purchase funnel. There was also a positive impact on page views, conversion rates, and average order value. The results underscore that rising customer expectations and the increasing use of smartphones are amplifying the need for mobile speed. The competitive gap will widen between brands that provide great mobile experiences and those that don't.


Summary of impact by vertical

All of the improvements below were seen after a 0.1 improvement in 4 metrics: Significant First Paint, Estimated Input Latency, Observed Load (Average page load time
in Google Analytics) and maximum server latency (time to first byte). Each page along the user journey had to improve each of these metrics by 0.1 seconds for these positive impacts to be seen.


With a 0.1 s improvement in site speed across all measured metrics, study participants saw an increase in progression rates (percentage of users moving from a web page to the next step in a funnel). conversion) in almost every step of the mobile journey. In particular, there was a 3.2% increase from the product listing page to the product detail page, and a 9.1% increase from the product detail page to the add to cart page. Retail consumers also spent 9.2% more, a spectacular increase.



Of all the verticals studied, the impact of the luxury verticals was the highest. However, it should be noted that progression rates on luxury sites tend to be quite small. Progression rates to contact page increased by 20.6% when site speed metrics improved by 0.1 second, and there was a significant 40.1% increase in users who moved from the details page of the contact. product to the Add to Cart page. Longer sessions were also recorded throughout the sailing trip.



Travel sites saw a 2.2% increase in check-out completion and a 10% improvement in booking rates.


Leading generation

Lead generation sites also experienced a positive impact across the board, with the biggest impact being a 21.6% improvement in the number of users advancing to the form submission page. There was also a 7% increase in page views.


About the study

The study was commissioned by Google and conducted by 55 and Deloitte. The goal of the study was to determine whether mobile site speed has an impact on brand revenue. The research team studied 37 leading brand sites in Europe and the United States and collected data on more than 30 million user sessions. The monitoring and analysis settings for each site were rigorously audited. There were no UX redesigns at any of the sites for the duration of the study. Mobile load times were monitored hour-by-hour for 30 days at the end of 2019. The results were consolidated in real time against a variety of typical revenue-related metrics drawn from each brand's analytics tool.

For more information, read the Milliseconds make millions report.

R Marketing Digital