Mobile-first indexing
What is mobile-first indexing?
Mobile-first indexing means Google uses the mobile version of a page’s content, crawled with its smartphone crawler, for indexing and ranking. Whatever is on your mobile page is what Google knows about, for searches on phones and on desktop computers.
Google started moving sites to mobile-first indexing in 2018 and announced the move complete in 2023. Since July 2024 it crawls and indexes all sites with Googlebot Smartphone. A site that does not work on mobile devices can no longer be indexed properly.
There is no separate mobile index. The name describes which version of a page Google reads first. For a responsive site, which serves the same HTML to every device, nothing changes. For sites with a separate mobile site (m.example.com) or dynamic serving that sends different HTML to phones, the mobile version must hold the same content, links, structured data and metadata as the desktop version.
Why mobile-first indexing matters for SEO
Content that only appears on desktop does not exist for Google. If your mobile template drops product descriptions, reviews, internal links or structured data to save space, Google indexes and ranks the slimmer page.
Blocking resources for the mobile crawler, lazy-loading content that only appears on interaction, or serving a broken mobile layout all hurt. A correct viewport meta tag and a responsive design are the simplest way to avoid the problem.
How to prepare for mobile-first indexing
- Use responsive design so every device gets the same HTML, and add a viewport meta tag.
- If you have a separate mobile site, make sure it has the same main content, headings, internal links, images with alt text, structured data, titles and meta descriptions as desktop.
- Keep meta robots tags the same on both versions. A noindex on the mobile page applies to the page in Google’s index.
- Do not hide important content behind interactions that Googlebot will not perform; content in tabs or accordions is fine if it is in the HTML.
- Check pages with the URL Inspection tool in Search Console, which shows what Googlebot Smartphone fetched.
Mobile-first indexing FAQ
Is mobile-first indexing complete?
Yes. Google announced the move complete in 2023, and since July 2024 it crawls and indexes all sites with its smartphone crawler.
Does mobile-first indexing mean desktop rankings do not matter?
No. Desktop searches still happen and are ranked separately, but the content Google uses for both comes from the mobile version of your page.
Is hidden content in tabs indexed on mobile?
Yes, as long as it is in the HTML. Google has said content in tabs and accordions on mobile is treated normally. Content that only loads after a tap is a different matter.
Related SEO terms
The viewport meta tag tells mobile browsers how to size and scale a page. Without it, phones show a shrunken desktop layout.
Googlebot is Google’s web crawler. It fetches pages so Google Search can index them, using a smartphone crawler for most sites.
Indexing is when a search engine analyses a crawled page and stores it in its index, so it becomes eligible to appear in search results.
Page speed is how quickly a page loads, shows its content and responds to input. Google measures it mainly through Core Web Vitals.
Lighthouse is Google’s open-source tool that tests a page in a lab and scores its performance, accessibility, best practices and SEO.