Components: Tab & Accordion

Guides tab and accordion implementation for organizing content without excessive vertical space. Two layout patterns: vertical accordion (FAQ-style, stacked) and horizontal tabs (how-to style, side-by-side). Both improve UX by reducing scroll; SEO impact depends on implementation and content placement.

When invoking: On first use, if helpful, open with 1–2 sentences on what this skill covers and why it matters, then provide the main output. On subsequent use or when the user asks to skip, go directly to the main output.

Layout Patterns

Pattern	Layout	Best for	Example
Vertical accordion	Stacked; expand/collapse one at a time	FAQ, Q&A, long lists, objection handling	"How do I return?" → answer below
Horizontal tabs	Side-by-side labels; one panel visible	How-to steps, product specs, pricing tiers, comparisons	"Step 1 \| Step 2 \| Step 3"

Mobile: Vertical accordion works well on small screens (natural scroll). Horizontal tabs can feel cramped—consider accordion, dropdown, or full-width tab bar that scrolls.

SEO: Is It Friendly?

Google's position: Google indexes and ranks content inside tabs and accordions fully; hidden content receives full weight (confirmed since 2016 mobile-first indexing). Gary Illyes: "we index the content, its weight is fully considered for ranking."

Practical nuance: Some tests show always-visible content outperforms hidden content in rankings. Reserve tabs/accordions for secondary content; place primary, keyword-critical content in visible areas.

Content type	Placement
Primary / ranking-focused	Visible above fold; not hidden
Secondary / supporting	Tabs, accordions acceptable
FAQ answers	Accordion OK; first item expanded by default; see faq-page-generator

Indexing Requirements

Content must be in the DOM on page load. Google does not simulate user clicks; it cannot "click" tabs to discover content.

Implementation	Indexed?
All tab content in HTML at load	✅ Yes
Content loaded via AJAX on tab click	❌ No

Recommendation: Server-render all tab content in the initial HTML; use CSS/JS only to show/hide. Prefer <details>/<summary> or equivalent server-rendered markup. See rendering-strategies for SSR, SSG, CSR and crawler visibility.

Horizontal Tabs: More Tabs, More Content?

Technically: Yes—if all content is in the DOM at load, more tabs = more indexable content. Mobile-first indexing gives full weight to tabbed content in HTML.

Strategically: Not always. Signal dilution occurs when many tabs = many different topics on one page. Google may struggle to understand which query the page should rank for; topical authority and keyword focus get spread thin.

Scenario	Use tabs?	Alternative
Same topic (How-to Step 1/2/3; product specs: dimensions, materials, shipping)	✅ Yes	—
Different topics (Service A, Service B, Portfolio, Blog)	❌ No	Separate URLs per topic; see content-strategy for pillar/cluster

When many horizontal tabs work: All tabs semantically related to one query (e.g., one how-to, one product). When to use separate pages: Each tab is a distinct topic deserving its own URL, crawl, and ranking opportunity.

Implementation

Native HTML (Recommended)

Use <details> and <summary>—no JavaScript required; accessible; crawlable.

<details open>
  <summary>First question (expanded by default)</summary>
  <p>Answer content here.</p>
</details>
<details>
  <summary>Second question</summary>
  <p>Answer content here.</p>
</details>

First tab/accordion: Add open attribute so it's expanded by default
<summary>: Must be first child of <details>; acts as toggle
Progressive enhancement: Style with CSS; add JS only if needed (e.g., close others when one opens)

JavaScript-Dependent Tabs

If using JS-only tabs: ensure all tab content is in the DOM at page load, not loaded via AJAX on click. Google does not simulate tab clicks. Prefer <details>/<summary> or server-rendered HTML. See rendering-strategies.

Avoid

Content loaded only after user click (AJAX, lazy-loaded via fetch)—crawlers will not index it
display: none or visibility: hidden for primary content—Google may treat differently
Many tabs with unrelated topics on one page—causes signal dilution; use separate URLs instead

Content Best Practices

Practice	Purpose
First item expanded	Ensures primary content visible on load; better for SEO and UX
Descriptive headers	`<summary>` / tab labels should clearly describe content; include keywords naturally
Logical structure	H2/H3 for sections; supports snippet extraction; see featured-snippet
Answer-first	For FAQ: 40–60 words direct answer; then detail; see faq-page-generator

Use Cases

Use case	Format	Layout	Notes
FAQ	Accordion	Vertical	FAQPage schema; first Q expanded; see faq-page-generator
How-to steps	Tabs	Horizontal	Step 1, Step 2, Step 3; sequential flow
Product specs	Tabs	Horizontal	Dimensions, materials, shipping—secondary to hero
Long guides	Accordion	Vertical	Collapsible sections; see toc-generator
Pricing tiers	Tabs	Horizontal	Compare plans; primary CTA visible
Objection handling	Accordion	Vertical	"What about X?"—supporting conversion

Schema & Rich Results

FAQ (vertical accordion): FAQPage JSON-LD; schema must match on-page content exactly; see schema-markup, faq-page-generator
How-to (horizontal tabs): HowTo schema for step-by-step content; see schema-markup, featured-snippet
Other tabs: No specific schema; ensure semantic HTML (headings, structure)

UX & Accessibility

Visual indicator: Arrow, plus/minus, or chevron to show expand/collapse state
Keyboard: <details>/<summary> natively keyboard-accessible
Core Web Vitals: Avoid layout shift (CLS) when expanding; reserve space or animate smoothly
Mobile: Touch targets ≥44×44px; vertical accordion often better than horizontal tabs on small screens (tabs can be cramped; accordion scrolls naturally)

Pre-Implementation Checklist

All tab/accordion content in DOM at page load (no AJAX on click)
Primary ranking content visible, not hidden
First tab/accordion expanded by default
Using <details>/<summary> or equivalent server-rendered HTML
Headers descriptive; keywords natural
Tabs share one topic (avoid signal dilution); if different topics, consider separate pages
For FAQ: FAQPage schema matches content

Related Skills

faq-page-generator: FAQ structure, answer length, schema; accordion is common FAQ UI
featured-snippet: Answer-first, H2/H3; content in accordions can be extracted
schema-markup: FAQPage for FAQ accordions; HowTo for step-by-step tabs
content-strategy: Pillar/cluster architecture; when to use separate pages vs tabs
toc-generator: Collapsible TOC; similar disclosure pattern
content-optimization: Word count, structure, multimedia in expandable sections
rendering-strategies: SSR, SSG, CSR; content in initial HTML for crawlers

tab-accordion