Collapse shows and hides content with a short animation. Point a button or link at the target with data-bs-toggle="collapse", keep aria-expanded and aria-controls in sync, and use it for read-more text, filter panels, sub-menus and expandable rows.
1Button toggle
A button with data-bs-toggle="collapse" shows and hides the target.
Cooking classes on Saturday mornings teach you our favourite recipes. Children are always welcome, with a menu made just for them.
<button class="btn btn-primary" type="button" data-bs-toggle="collapse" data-bs-target="#collapse-908" aria-expanded="false" aria-controls="collapse-908">Toggle details</button>
<div class="collapse" id="collapse-908">
<div class="card card-body mt-2">
Cooking classes on Saturday mornings teach you our favourite recipes. Children are always welcome, with a menu made just for them.
</div>
</div>2Link toggle
A link with href="#id" and role="button" works the same way.
What does this mean?
Vegan, vegetarian and gluten-free dishes are marked clearly on every menu.
<a class="link-primary" data-bs-toggle="collapse" href="#collapse-909" role="button" aria-expanded="false" aria-controls="collapse-909"><i class="bi bi-info-circle" aria-hidden="true"></i> What does this mean?</a>
<div class="collapse" id="collapse-909">
<p class="small text-body-secondary mt-2 mb-0">Vegan, vegetarian and gluten-free dishes are marked clearly on every menu.</p>
</div>3Horizontal collapse
collapse-horizontal animates the width; the content needs a fixed width.
Book a table online in seconds, or call us for groups of eight or more.
<button class="btn btn-outline-primary" type="button" data-bs-toggle="collapse" data-bs-target="#collapse-910" aria-expanded="false" aria-controls="collapse-910">Toggle width</button>
<div style="min-height: 110px;" class="mt-2">
<div class="collapse collapse-horizontal" id="collapse-910">
<div class="card card-body" style="width: 260px;">
Book a table online in seconds, or call us for groups of eight or more.
</div>
</div>
</div>4Multiple targets
One button can toggle several elements by targeting a shared class.
Bread is baked every morning and pasta is rolled by hand in our kitchen.
Order for pickup or delivery and enjoy the same dishes at home.
<div class="d-flex flex-wrap gap-2 mb-2">
<button class="btn btn-outline-secondary" type="button" data-bs-toggle="collapse" data-bs-target="#multi-911" aria-expanded="false" aria-controls="multi-911">Toggle first</button>
<button class="btn btn-outline-secondary" type="button" data-bs-toggle="collapse" data-bs-target="#multi-912" aria-expanded="false" aria-controls="multi-912">Toggle second</button>
<button class="btn btn-primary" type="button" data-bs-toggle="collapse" data-bs-target=".multi-group-913" aria-expanded="false" aria-controls="multi-911 multi-912">Toggle both</button>
</div>
<div class="row g-2">
<div class="col-sm-6">
<div class="collapse multi-group-913" id="multi-911">
<div class="card card-body">
Bread is baked every morning and pasta is rolled by hand in our kitchen.
</div>
</div>
</div>
<div class="col-sm-6">
<div class="collapse multi-group-913" id="multi-912">
<div class="card card-body">
Order for pickup or delivery and enjoy the same dishes at home.
</div>
</div>
</div>
</div>5Read more
Show the first part of a text and reveal the rest on demand.
Our team has done this many times, so you never have to guess. Friendly people answer your questions quickly, by phone, chat or email.
Thousands of guests already trust us, and we work hard to keep it that way. Cooking classes on Saturday mornings teach you our favourite recipes. We listen first, then build a plan around what you actually need.
<p class="mb-1">Our team has done this many times, so you never have to guess. Friendly people answer your questions quickly, by phone, chat or email.</p>
<div class="collapse" id="more-914">
<p class="mb-1">Thousands of guests already trust us, and we work hard to keep it that way. Cooking classes on Saturday mornings teach you our favourite recipes. We listen first, then build a plan around what you actually need.</p>
</div>
<button class="btn btn-link px-0 ca-more" type="button" data-bs-toggle="collapse" data-bs-target="#more-914" aria-expanded="false" aria-controls="more-914"><span class="ca-more-show">Read more</span><span class="ca-more-hide">Show less</span></button>6Filter panel
A filter button above a table reveals extra search fields.
<div class="d-flex gap-2">
<input type="search" class="form-control" placeholder="Search orders" aria-label="Search orders" style="max-width: 280px;">
<button class="btn btn-outline-secondary" type="button" data-bs-toggle="collapse" data-bs-target="#filters-915" aria-expanded="false" aria-controls="filters-915"><i class="bi bi-sliders" aria-hidden="true"></i> Filters</button>
</div>
<div class="collapse" id="filters-915">
<div class="border rounded p-3 mt-2 row g-2">
<div class="col-sm-6">
<label class="form-label small" for="filter-q-916">Customer</label>
<input class="form-control form-control-sm" id="filter-q-916" type="text" placeholder="Luna Nguyen">
</div>
<div class="col-sm-6">
<label class="form-label small" for="filter-status-917">Status</label>
<select class="form-select form-select-sm" id="filter-status-917">
<option>Any</option>
<option>Paid</option>
<option>Pending</option>
<option>Refunded</option>
</select>
</div>
<div class="col-12 text-end">
<button type="button" class="btn btn-primary btn-sm">Apply</button>
</div>
</div>
</div>7Sidebar sub-menus
Nested navigation where each section expands to show its links.
<nav class="border rounded p-2" style="max-width: 260px;" aria-label="Admin menu">
<ul class="nav flex-column">
<li class="nav-item"><a class="nav-link link-body-emphasis" href="#"><i class="bi bi-house" aria-hidden="true"></i> Home</a></li>
<li class="nav-item"><a class="nav-link link-body-emphasis d-flex justify-content-between" data-bs-toggle="collapse" href="#menu-918" role="button" aria-expanded="true" aria-controls="menu-918"><span><i class="bi bi-bag" aria-hidden="true"></i> Sales</span><i class="bi bi-chevron-down" aria-hidden="true"></i></a><div class="collapse show" id="menu-918"><ul class="nav flex-column ms-4 small"><li class="nav-item"><a class="nav-link py-1" href="#">Orders</a></li><li class="nav-item"><a class="nav-link py-1" href="#">Invoices</a></li></ul></div></li>
<li class="nav-item"><a class="nav-link link-body-emphasis d-flex justify-content-between" data-bs-toggle="collapse" href="#menu-919" role="button" aria-expanded="false" aria-controls="menu-919"><span><i class="bi bi-bar-chart" aria-hidden="true"></i> Reports</span><i class="bi bi-chevron-down" aria-hidden="true"></i></a><div class="collapse" id="menu-919"><ul class="nav flex-column ms-4 small"><li class="nav-item"><a class="nav-link py-1" href="#">Weekly</a></li><li class="nav-item"><a class="nav-link py-1" href="#">Monthly</a></li></ul></div></li>
</ul>
</nav>8Expandable table rows
A detail row under each table row opens with a small toggle.
| Invoice | Amount | Details |
|---|---|---|
| #ORD-3715 | $566.36 | |
Billed to Kenji Novak, Dublin. Due Jan 3, 2027. | ||
| #INV-6480 | $367.05 | |
Billed to Arjun Fischer, Porto. Due Jan 12, 2027. | ||
<div class="table-responsive">
<table class="table align-middle mb-0">
<thead>
<tr>
<th scope="col">Invoice</th>
<th scope="col">Amount</th>
<th scope="col"><span class="visually-hidden">Details</span></th>
</tr>
</thead>
<tbody>
<tr>
<td>#ORD-3715</td>
<td>$566.36</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-bs-toggle="collapse" data-bs-target="#row-detail-920" aria-expanded="false" aria-controls="row-detail-920"><i class="bi bi-chevron-expand" aria-hidden="true"></i><span class="visually-hidden">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="collapse" id="row-detail-920"><div class="p-3 bg-body-tertiary small">Billed to Kenji Novak, Dublin. Due Jan 3, 2027.</div></div></td>
</tr>
<tr>
<td>#INV-6480</td>
<td>$367.05</td>
<td class="text-end"><button class="btn btn-sm btn-light border" type="button" data-bs-toggle="collapse" data-bs-target="#row-detail-921" aria-expanded="false" aria-controls="row-detail-921"><i class="bi bi-chevron-expand" aria-hidden="true"></i><span class="visually-hidden">Show details</span></button></td>
</tr>
<tr>
<td colspan="3" class="p-0 border-0"><div class="collapse" id="row-detail-921"><div class="p-3 bg-body-tertiary small">Billed to Arjun Fischer, Porto. Due Jan 12, 2027.</div></div></td>
</tr>
</tbody>
</table>
</div>9Advanced form options
Hide rarely used settings behind an "Advanced" toggle.
<div style="max-width: 420px;">
<a class="small" data-bs-toggle="collapse" href="#advanced-922" role="button" aria-expanded="false" aria-controls="advanced-922"><i class="bi bi-gear" aria-hidden="true"></i> Advanced options</a>
<div class="collapse" id="advanced-922">
<div class="mt-2">
<label class="form-label small" for="adv-slug-923">URL slug</label>
<input class="form-control form-control-sm mb-2" id="adv-slug-923" type="text" value="the-small-habits-that-make-a-big-difference">
<div class="form-check">
<input class="form-check-input" type="checkbox" id="adv-index-924">
<label class="form-check-label small" for="adv-index-924">Hide from search engines</label>
</div>
</div>
</div>
</div>10Minimisable card
A header button collapses the card body, as in dashboard widgets.
Traffic
60.0k
6% this week
<div class="card" style="max-width: 26rem;">
<div class="card-header d-flex justify-content-between align-items-center">
<span class="fw-semibold"><i class="bi bi-graph-up" aria-hidden="true"></i> Traffic</span>
<button class="btn btn-sm btn-link link-secondary p-0" type="button" data-bs-toggle="collapse" data-bs-target="#widget-925" aria-expanded="true" aria-controls="widget-925"><i class="bi bi-dash-square" aria-hidden="true"></i><span class="visually-hidden">Minimise</span></button>
</div>
<div class="collapse show" id="widget-925">
<div class="card-body">
<div class="fs-3 fw-bold">
60.0k
</div>
<div class="small text-success">
<i class="bi bi-arrow-up" aria-hidden="true"></i> 6% this week
</div>
</div>
</div>
</div>11Open by default
Add .show to start expanded; the button's aria-expanded is then true.
Order for pickup or delivery and enjoy the same dishes at home. Thousands of guests already trust us, and we work hard to keep it that way.
<button class="btn btn-outline-dark btn-sm" type="button" data-bs-toggle="collapse" data-bs-target="#collapse-926" aria-expanded="true" aria-controls="collapse-926">Hide summary</button>
<div class="collapse show" id="collapse-926">
<div class="alert alert-secondary mt-2 mb-0">
Order for pickup or delivery and enjoy the same dishes at home. Thousands of guests already trust us, and we work hard to keep it that way.
</div>
</div>12Rotating chevron
A chevron that turns when the panel opens, driven by aria-expanded in CSS.
Our menu changes with the seasons and the best produce from nearby farms.
<button class="btn btn-light border w-100 d-flex justify-content-between align-items-center ca-chev" type="button" data-bs-toggle="collapse" data-bs-target="#collapse-927" aria-expanded="false" aria-controls="collapse-927" style="max-width: 420px;">Shipping & returns<i class="bi bi-chevron-down" aria-hidden="true"></i></button>
<div class="collapse" id="collapse-927" style="max-width: 420px;">
<div class="p-3 small">
Our menu changes with the seasons and the best produce from nearby farms.
</div>
</div>13Comments thread
Keep a feed short and let readers open the replies.
Start in minutes and get help from a real person whenever you need it.
View 2 replies
Owen Hughes Children are always welcome, with a menu made just for them.
Ethan Larsen Every detail is handled by people who care about getting it right.
<p class="mb-1">Start in minutes and get help from a real person whenever you need it.</p>
<a class="small" data-bs-toggle="collapse" href="#comments-928" role="button" aria-expanded="false" aria-controls="comments-928"><i class="bi bi-chat" aria-hidden="true"></i> View 2 replies</a>
<div class="collapse" id="comments-928">
<div class="mt-2 ps-3 border-start">
<div class="d-flex gap-2 mb-2">
<img src="../assets/img/avatar-8.svg" alt="Owen Hughes" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Owen Hughes</strong> Children are always welcome, with a menu made just for them.
</div>
</div>
<div class="d-flex gap-2 mb-2">
<img src="../assets/img/avatar-5.svg" alt="Ethan Larsen" class="rounded-circle flex-shrink-0" width="32" height="32">
<div class="bg-body-tertiary rounded p-2 small">
<strong>Ethan Larsen</strong> Every detail is handled by people who care about getting it right.
</div>
</div>
</div>
</div>14Release notes
A compact version line that expands into the full change list.
Version 3.1 Stable
Jul 4, 2026
- Chef's specials
- Online reservations
- Faster loading on slow connections
<div class="border rounded p-3">
<div class="d-flex justify-content-between align-items-center">
<div>
<span class="fw-semibold">Version 3.1</span> <span class="badge text-bg-success">Stable</span>
<div class="small text-body-secondary">
Jul 4, 2026
</div>
</div>
<button class="btn btn-outline-primary btn-sm" type="button" data-bs-toggle="collapse" data-bs-target="#notes-929" aria-expanded="false" aria-controls="notes-929">What's new</button>
</div>
<div class="collapse" id="notes-929">
<ul class="small mt-3 mb-0">
<li>Chef's specials</li>
<li>Online reservations</li>
<li>Faster loading on slow connections</li>
</ul>
</div>
</div>15Specification list
A definition list of technical details hidden behind a full-width toggle.
- Weight
- 2.4 kg
- Dimensions
- 31 x 26 x 10 cm
- Warranty
- 3 years
<button class="btn btn-outline-secondary w-100" type="button" data-bs-toggle="collapse" data-bs-target="#specs-930" aria-expanded="false" aria-controls="specs-930"><i class="bi bi-list-columns-reverse" aria-hidden="true"></i> Full specifications</button>
<div class="collapse" id="specs-930">
<dl class="row small border rounded p-3 mt-2 mb-0">
<dt class="col-sm-4">Weight</dt>
<dd class="col-sm-8">2.4 kg</dd>
<dt class="col-sm-4">Dimensions</dt>
<dd class="col-sm-8">31 x 26 x 10 cm</dd>
<dt class="col-sm-4">Warranty</dt>
<dd class="col-sm-8 mb-0">3 years</dd>
</dl>
</div>16Expandable search bar
A search icon in a header opens a full-width search field below it.
Iris Hub
<div class="border rounded">
<div class="d-flex align-items-center justify-content-between p-2">
<span class="fw-bold">Iris Hub</span>
<button class="btn btn-light" type="button" data-bs-toggle="collapse" data-bs-target="#msearch-931" aria-expanded="false" aria-controls="msearch-931"><i class="bi bi-search" aria-hidden="true"></i><span class="visually-hidden">Search</span></button>
</div>
<div class="collapse" id="msearch-931">
<div class="p-2 border-top">
<label class="visually-hidden" for="msearch-input-932">Search</label>
<input type="search" class="form-control" id="msearch-input-932" placeholder="Search Iris Hub">
</div>
</div>
</div>17Onboarding checklist
Each checklist step expands to explain what to do.
Clear prices, honest advice and no surprises along the way.
Every dish is cooked to order, so tell us if you would like anything changed.
Our team has done this many times, so you never have to guess.
<div class="list-group" style="max-width: 480px;">
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-bs-toggle="collapse" data-bs-target="#step-933" aria-expanded="false" aria-controls="step-933"><span class="text-success"><i class="bi bi-check-circle-fill" aria-hidden="true"></i></span>Verify your email</button>
<div class="collapse" id="step-933">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Clear prices, honest advice and no surprises along the way.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-bs-toggle="collapse" data-bs-target="#step-934" aria-expanded="false" aria-controls="step-934"><span class="text-body-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Add a payment method</button>
<div class="collapse" id="step-934">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Every dish is cooked to order, so tell us if you would like anything changed.</p>
</div>
</div>
<div class="list-group-item">
<button class="btn btn-link p-0 text-decoration-none link-body-emphasis d-flex align-items-center gap-2 w-100 text-start" type="button" data-bs-toggle="collapse" data-bs-target="#step-935" aria-expanded="false" aria-controls="step-935"><span class="text-body-tertiary"><i class="bi bi-circle" aria-hidden="true"></i></span>Invite a teammate</button>
<div class="collapse" id="step-935">
<p class="small text-body-secondary mt-2 mb-1 ms-4">Our team has done this many times, so you never have to guess.</p>
</div>
</div>
</div>18Swap two panels
Two collapses sharing a class swap places: one hides while the other shows.
Read-only view: Bread is baked every morning and pasta is rolled by hand in our kitchen.
<div class="pane-group-938">
<div class="collapse show pane-group-938-p" id="pane-936">
<div class="card card-body">
<p><i class="bi bi-eye" aria-hidden="true"></i> Read-only view: Bread is baked every morning and pasta is rolled by hand in our kitchen.</p>
<button class="btn btn-primary btn-sm align-self-start" type="button" data-bs-toggle="collapse" data-bs-target=".pane-group-938-p" aria-expanded="true" aria-controls="pane-936 pane-937"><i class="bi bi-pencil" aria-hidden="true"></i> Edit</button>
</div>
</div>
<div class="collapse pane-group-938-p" id="pane-937">
<div class="card card-body">
<label class="form-label" for="pane-937-text">Description</label>
<textarea class="form-control mb-2" id="pane-937-text" rows="2">Our sommelier has paired each dish with wines from small family vineyards.</textarea>
<button class="btn btn-success btn-sm align-self-start" type="button" data-bs-toggle="collapse" data-bs-target=".pane-group-938-p" aria-expanded="false" aria-controls="pane-936 pane-937"><i class="bi bi-check-lg" aria-hidden="true"></i> Done</button>
</div>
</div>
</div>19Grouped notifications
Older notifications collapse into a single "show earlier" row.
- Vegan, vegetarian and gluten-free dishes are marked clearly on every menu.
- Private dining rooms seat up to forty guests for birthdays and business dinners.
- Book a table online in seconds, or call us for groups of eight or more.
<ul class="list-group" style="max-width: 420px;">
<li class="list-group-item small"><i class="bi bi-bell" aria-hidden="true"></i> Vegan, vegetarian and gluten-free dishes are marked clearly on every menu.</li>
<li class="list-group-item p-0"><div class="collapse" id="group-939"><ul class="list-group list-group-flush"><li class="list-group-item small text-body-secondary">Private dining rooms seat up to forty guests for birthdays and business dinners.</li><li class="list-group-item small text-body-secondary">Book a table online in seconds, or call us for groups of eight or more.</li></ul></div><button class="btn btn-link btn-sm w-100" type="button" data-bs-toggle="collapse" data-bs-target="#group-939" aria-expanded="false" aria-controls="group-939">Show 6 earlier</button></li>
</ul>20Nested collapse
A collapse inside another for drilling into details step by step.
Friendly people answer your questions quickly, by phone, chat or email.
- Design: $4,954.59
- Development: $16,353.55
- Marketing: $4,951.22
<button class="btn btn-outline-primary" type="button" data-bs-toggle="collapse" data-bs-target="#outer-940" aria-expanded="false" aria-controls="outer-940">Project details</button>
<div class="collapse" id="outer-940">
<div class="card card-body mt-2">
<p>Friendly people answer your questions quickly, by phone, chat or email.</p>
<button class="btn btn-sm btn-outline-secondary align-self-start" type="button" data-bs-toggle="collapse" data-bs-target="#inner-941" aria-expanded="false" aria-controls="inner-941">Budget breakdown</button>
<div class="collapse" id="inner-941">
<ul class="small mt-2 mb-0">
<li>Design: $4,954.59</li>
<li>Development: $16,353.55</li>
<li>Marketing: $4,951.22</li>
</ul>
</div>
</div>
</div>