Are accordions and tabs really taken into account by Google in mobile-first indexing?

Why is Google changing its stance on hidden content?

Historically, Google penalized hidden content or considered it less important. The idea was simple: if a user does not see content immediately, it is deemed secondary or manipulative. Accordions and tabs fell into this suspicious category.

The shift to mobile-first indexing has disrupted this logic. On mobile, screen space is limited. Hiding content in accordions is no longer a questionable tactical choice; it is an ergonomic necessity. Google has therefore had to adapt its processing to avoid undervaluing perfectly legitimate pages.

What changes concretely for indexing?

Previously, a block of text hidden behind a tab had less semantic weight than a paragraph visible directly. Google crawled it, certainly, but assigned it a lower value in relevance calculations.

With mobile-first, this content is supposed to be treated equally with the rest of the page. This means that a strategic keyword placed in an accordion can theoretically contribute to ranking just as much as a keyword in the main body. Theoretically.

Should we conclude that all hidden content is now equivalent?

No. Google does not claim that the display order or depth of interaction no longer matters. Content accessible with the first click in an accordion immediately visible at the top of the page is likely not treated the same as content buried at the 5th level of a dropdown menu.

Mueller's statement remains vague on internal prioritization criteria. It is likely that Google still applies weighting based on perceived visibility, user engagement (actual expansion of accordions), and semantic consistency with the rest of the content.

• Mobile-first indexing requires a reassessment of hidden content for ergonomic reasons
• Content in accordions and tabs can now affect rankings like visible content
• No guarantee that all hidden content will be treated equally: depth and accessibility likely still matter
• Google has never published a clear weighting grid between immediately visible content and click-accessible content
• This evolution mainly concerns mobile-first compliant sites, not poorly optimized legacy desktop sites

Is this statement consistent with real-world observations?

Yes and no. Since the full rollout of mobile-first indexing, several tests have shown that relevant content in accordions appears in SERPs. Featured snippets even extract text located in tabs that are closed by default.

But other observations contradict the idea of strict equality. In highly competitive queries, pages with immediately visible content seem to retain an advantage. It’s hard to tell if this is related to the treatment of hidden content or to other signals (engagement, CTR, dwell time). [To verify] with proper A/B tests on homogeneous corpuses.

What nuances should be added to Mueller's statement?

First, Mueller speaks of “may be treated”, not “is always treated”. This is a crucial nuance. Google reserves the right to interpret. If your accordion hides 10,000 words of spam keywords, it will not be valued as legitimate content.

Next, the aspect of user experience remains essential. Content hidden by default but never opened by users sends a negative signal. Google incorporates interaction metrics into its algorithms. A relevant accordion that generates clicks and engagement will be treated better than an ignored accordion.

In what cases does this rule not fully apply?

If your site is not mobile-first compliant, this statement only concerns you partially. Google still crawls some sites in a desktop-first version (though this is now marginal). In this case, the old processing may persist.

Moreover, content hidden via complex CSS or JavaScript is not always indexable correctly, even in mobile-first. If your accordion requires heavy JavaScript interaction that Googlebot struggles to simulate, content may remain invisible. Use Google Search Console’s mobile rendering testing tools to check.

What should you do concretely with accordions and tabs?

First, audit your hidden content. Identify all important text blocks hidden in accordions, tabs, or modals. Ensure they are crawlable and indexable via a rendering test in Search Console. If Google can't see them, your editorial work is lost.

Second, prioritize mobile readability. Accordions are legitimate for structuring dense content on mobile, but do not systematically hide everything. A good balance: keep the introduction of each section visible, and offer the accordion for details. This optimizes both UX and crawl.

What mistakes should absolutely be avoided?

Do not give in to the temptation to hide low-quality content in accordions hoping that Google will ignore it. The opposite may happen: Google indexes it, detects the low quality, and degrades the overall page score.

Avoid too deep accordions (accordion in accordion in accordion). Google can theoretically crawl them, but the UX is catastrophic and engagement signals will be weak. Stick to one level of depth, two maximum in very specific cases (complex FAQs, for example).

How can you verify that your site is compliant and optimized?

Use Google Search Console, under the “URL Inspection” tab, to test the mobile rendering of your pages with accordions. Look at the rendered screenshot and the analyzed HTML. If your hidden content appears in the DOM and is readable by Googlebot, that’s a good sign.

Complement this with a position monitoring tool for queries specifically targeting the content present in your accordions. If you rank for these queries, it means Google is indexing and valuing this content. If not, dig deeper: technical issue, lack of relevance, or too strong competition.

• Check that all accordions are crawlable via JavaScript rendering using Search Console
• Ensure that the hidden content remains relevant and of quality, not just filler
• Prefer a limited depth level (1 click, 2 maximum) to maintain accessibility
• Regularly test the mobile rendering of your pages to detect any display or crawl bugs
• Monitor the Core Web Vitals: poorly coded accordions can degrade CLS or LCP
• Use HTML5 semantic tags (details/summary) for native accordions, better supported by crawlers