Accordion

Definition

An accordion is a vertically stacked set of panels. Each panel has a trigger (the clickable header) and content (the section that expands and collapses). Users open one or more panels to reveal detail while keeping the rest of the stack compact.

The pattern is progressive disclosure: show structure and labels first, reveal detail on demand. Whether only one panel or several can stay open at once is a configuration choice — not a different component.

Also known as

People also call this a collapsible list, expandable sections, or expansion panels. Disclosure group is another name — though disclosure often implies a single open/close pair rather than a full stacked set.

Component Anatomy

When to use it

Use an accordion when related content does not all need to be visible at once:

• FAQs — users scan questions and open only what they need
• Settings groups — organize many options without a long scroll
• Dense reference material — keep a single page navigable (specs, docs, help)
• Forms with optional sections — advanced or rarely used fields stay tucked away
• Mobile or narrow layouts — vertical stacking uses limited width well

Avoid an accordion when users need to compare content across sections at the same time, when every section must stay visible (use tabs, cards, or a flat layout instead), or when the list is very short — plain headings may be enough.

Single-expand keeps only one panel open at a time (common for FAQs). Multi-expand allows several panels open together (common for settings or reference).