Ecommerce Quarterly Benchmarks for 1Q2019 published by e-commerce software providers Monetate show that although 55% of visits by Americans to e-commerce websites occurred on mobile phones, the average mobile conversion rate was only 40% of that on desktops.

Here's a further breakdown of data for mobile phones vs. desktops in the USA, the UK and globally:

Obviously, many websites aren't performing as well for mobile users as they do for desktop users, as evidenced by fewer pageviews, lower conversion rates and smaller order sizes on mobile.

An analysis by Google recommends using a Relative Mobile Conversion Rate (Rel mCvR) metric to show stakeholders that there's a revenue gap the company needs to close by improving the performance of its website on mobile:

Rel mCvR = Mobile Conversion Rate / Desktop Conversion Rate

which is where we got the 40% figure mentioned above:

1.79% Mobile Conversion Rate / 4.44% Desktop Conversion Rate = 0.403 or 40%

Google identifies 2 categories of influencers of conversion rate:

• Traffic influencers, like channel mix, marketing campaign, seasonality
• Website performance, including user experience and site speed

But if traffic influencers are the same for all website users - as would normally be the case - then website performance alone should determine relative conversion rates for mobile vs. desktop.

Google offers these further tips:

• Watch desktop conversion rate as well as Rel mCvR, as a technical problem that affects desktop users could improve Rel mCvR with no improvement in mobile conversion rate.
• Track rel mCvR weekly, as site improvement will be a long-term process and daily data will be too volatile.
• If offline conversions are possible (so that mobile devices are often being used for research only), 70% Rel mCvR might be a reasonable target.

Next steps Google recommends:

• Start mobile A/B testing.
• Use the process described at the Google Optimize Resource Hub
• Read the case studies here.
• Use Google Optimize.

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Comment: Undeniably, the numbers from Monetate show that, on average, websites intended to make sales perform significantly better on desktop than on mobile devices. How's your website converting?