How to Optimize for the Mobile-first Index

Feb 6, 2018


min read

The start of the New Year has been awash with talk of the impending switch to the mobile-first index. Although it has been on the radar since November 2016, this year is when the mobile-first index is expected to be rolled out to all sites.

So, are you ready?

2018 is going to be the year of the mobile. Whilst many sites have been ‘mobile friendly' for some time now, Google is really pushing on with their drive to create a mobile-friendly web for all users, and this switch to a mobile-first index is their way of forcing websites to comply. It is going to be a great thing for users moving forward; however, in the short term, there could be some pain.

The good news is there is still time to get your website ready. Google is rolling the launch of the mobile-first index out very slowly. In fact, they started towards the end of 2017, rolling out the index to sites that were ‘ready’ enough for the change to have a minimal impact.

As we move into 2018, Google will start to roll out the mobile-first index across more and more sites, but this phased roll out will give webmasters time to get their site in order.

What is the mobile-first index?

Just a quick recap for those who may not have been keeping up to date.

The mobile-first index is, as the name suggests, Google's move to determine your rankings based on the indexing of your mobile site. Currently, all rankings are taken from the desktop version of your site, even your mobile rankings.

The mobile-first index will take your mobile site first (whether this is an or a responsive site) and you may well see an increase in Smartphone Googlebot crawls to your site (an early indicator that the mobile-first index has been rolled out on your site).

Also, as the name suggests, this is not a mobile ‘only' index. If you do not have a mobile-friendly website, Google will default to crawling your desktop site in order to rank your pages.

However, be warned, the lack of a mobile-friendly site is likely to count against you in terms of your ability to rank, as the focus is on delivering a better user experience to mobile users.

For a lot of sites, there won’t be a huge shift. For anyone who has a responsive site, the content on desktop and mobile is typically exactly the same. If, however, you have an site, you may choose to show less content to users who visit on mobile, in order to provide a better UX.

If the content you choose not to show has strong SEO benefits on desktop, you are going to need to take a close look at this and work out how to bridge that content gap whilst still providing an awesome UX.

What should I do about mobile-first indexing?

If you have an site or if your responsive site does not deliver the exact same content on a mobile device, you have some work to do. Even if your responsive site is exactly the same on mobile and desktop, we would still recommend auctioning some of the tips below in order to improve the UX on mobile and ensure your content has the best possible chance of ranking in Google’s mobile-first index.

3 Key areas to focus on to optimize for the mobile-first index

OK, so whether you have an site or a responsive site, these are the three key areas we think you need to focus on in order to prepare for the move to the mobile-first index.

Make it part of your return to work plan to make a start on these at the beginning of the year. Whilst no deadline has been put in place for the roll out of mobile-first indexing, we expect a lot of sites to start seeing the changes in the first quarter of the year so the sooner you can get on this, the better.

1. Site Speed

Google’s aim with the mobile-first index is to create a better UX on mobile devices. With mobile search overtaking desktop search, this makes a lot of sense. One key area they are trying to improve is the page load speed.

A fast loading site on mobile will often provide a much better UX (as long as the content is relevant) so any improvements you can make to either your site or your mobile responsive site will help prepare for the mobile-first index.

Here are four ways you can speed up your site on mobile:

1.1 AMPThe Accelerated Mobile Pages (AMP) Project is an open source initiative to improve the mobile ecosystem. Thanks to the pared-down HTML that is used by AMP, it allows you to load your web pages much faster than regular HTML. Google also caches your content within their own cache to speed up load time even more. All this results in a much faster, sleeker user experience and should, in turn, lead to improved visibility in the search results.


If you manage a WordPress site, there is a pretty awesome plugin that will convert your pages to AMP as well as Instant Articles for Facebook.


If you manage a WordPress site, there is a pretty awesome plugin that will convert your pages to AMP as well as Instant Articles for Facebook.


If you manage a WordPress site, there is a pretty awesome plugin that will convert your pages to AMP as well as Instant Articles for Facebook.

1.2 PWAProgressive Web Apps (PWAs) are an alternative to moving to AMP. Their main selling points include:

  • Reliable – loads instantly

  • Fast – responds quickly to user interactions

  • Engaging – feels like a natural app on a device with an immersive UX

You can find out more about PWAs on the Google Developers Website or watch this cool video.

1.3  PWAMP(!) - a term first introduced by Google’s Gary Illyes at SMX Seattle, PWAMP is a combination of a PWA built on AMP HTML, JS and CSS. Whilst PWAMP sites may not validate as AMP pages, they are lightning fast and provide all the benefits of a PWA as listed above. They could be the future and one to keep an eye on. Read more about PWAMP here.

1.4 Do nothing – if you have worked hard to get your current mobile experience (kudos to you) then there may well be very little benefit to going down any of the above routes. All Google is trying to do is ensure that the mobile web is quick, secure and provides a good user experience. If you are already doing this, there is probably very little benefit to changing anything.

2. Content

The next key area to focus on is the content itself. In order to rank your content from your mobile site, Google needs to be able to access it. That means you need to make sure the mobile version of your site has all the high-quality, valuable content that exists on your desktop site including images, videos, links and copy. Make sure all the content is crawlable and indexable.

In order to find out if there are any differences between the content that Google sees on your desktop site and mobile site, you can use the awesome Screaming Frog tool to find out where those gaps appear.

Simply crawl your site using the different user agents and then analyse these results. Moz recently published an awesome blog post on conducting parity audits that could just save your bacon.

There are of course a few things you can be doing now to make sure your site is ready for the mobile-first index.

Here are four of our top tips:

  • Use accordion and drop-down menus appropriately – Google has already said that sites will not be punished for ‘hiding' content behind an accordion or drop-down menu (as long as the content behind them loads when the page first loads). They understand that real estate is limited on mobile so it makes sense not to show users everything all at once. They have also said that they will crawl all content that is contained within drop downs, so use them wisely as part of your mobile design.

  • Never use Flash – this should be a given but we still see sites who insist on using Flash. Apple killed Flash from mobile, and since a high percentage of mobile users can’t see Flash content, why continue to use it? Use HTML5 or Java to add those cool interactive elements that can be super-engaging.

  • Consider your use of pop-ups on mobile – there is definitely a time and a place for pop-ups. If you are a business that relies on your website for lead generation, they can be a crucial part of the UX to get people to sign up for something. They can also be completely annoying, especially when they stop a user getting to where they want to go. Consider where in the user journey you decide to display a pop-up and consider what the user is likely to be doing when one appears.

  • Consider the text size, tap target and padding – there are few  things more annoying than hitting the wrong button when you are trying to navigate somewhere on a mobile device. Make sure your website is ‘finger-friendly’ by sizing your tap targets appropriately and leaving enough padding between clickable elements on your site. You can read more here about designing and developing for the mobile-first index.

3. Technical

The final area to focus on are the technical elements of your mobile set-up. There are a number of areas to consider, and making sure that you are deploying the same technical elements on your mobile site as you are on desktop will be crucial.

Here are a few areas to focus on:

  • Structured Data – if you are using structured data markup on your desktop site, you also need to make sure this is deployed on mobile too. URLs shown within structured data on mobile pages should be the mobile version of the URL.

  • Metadata – ensure that the key metadata elements (page titles and meta description) are equivalent on both versions of your pages. The reason Google recommends 'equivalent' rather than 'identical' is to potentially optimize your titles for the shorter real estate in the mobile SERPs. However, you do need to make sure you are including the same keywords in your page titles on mobile.

  • Hreflang – if you use the rel=hreflang tag to send users to relevant international-specific pages, then you need to ensure that your mobile URL’s hreflang tag points to the mobile version of your country/language variant and the same for desktop.

  • Social Tags – Open Graph Tags and Twitter cards (as well as other social metadata) should be included on the mobile as well as the desktop version of the site.

  • XML Sitemap and robots.txt – make sure any links to your XML sitemap are accessible from the mobile version of your site. The same applies to the robots.txt file as there could be ramifications if this is not accessible and you have pages that you control using the disallow command or other key instructions.

  • Google Search Console Verification – if you currently only verify your desktop site in Google Search Console, you will need to ensure the mobile version of the site is also verified so you can get live, up to date information about crawling, indexing and any issues on your site.

You can check out more of the key questions around the mobile-first index launch on this recent blog by Moz.


The mobile-first index is coming this year so now is the time to get to action. Get stuck into a parity audit of your desktop and mobile sites, highlight any potential issues then get to work on fixing those issues along with making those all-important site speed improvements and you will find that you will soon be set for the change.

Keep an eye on your traffic from Smartphone Googlebot – if you see an increase, then you can be fairly certain that Google is testing out the mobile-first index on your site so be prepared!

Note: The opinions expressed in this article are the views of the author, and not necessarily the views of Caphyon, its staff, or its partners.

Article by

Gavin Hirst

Gavin Hirst is a Brit working abroad. He is a copywriter, SEO and content marketing expert working for one of Auckland’s leading digital marketing agencies, Digital Hothouse in New Zealand. Outside of work, Gavin is a keen golfer and is passionate about the outdoors – hence the move to NZ! Connect with Gavin on LinkedIn or with Digital Hothouse on Twitter and keep up to date with all the latest digital marketing news and trends in NZ and across the world.

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