shadcn-html / checkbox

Built with: CSS

Checkbox

A control that toggles between checked and unchecked. Built on native <input type="checkbox"> with CSS-only checkmark.

Component Skill — components/checkbox/component-skill.md

Native basis

<input type="checkbox"> element styled with CSS appearance: none.

Web Platform APIs

Classes

.checkbox

Accessibility

• The native <input type="checkbox"> provides all keyboard and screen reader support.

• Use <label> with for to associate the label text.

• Use <fieldset> + <legend> for checkbox groups.

• Use aria-invalid="true" for validation errors.

• Use indeterminate property via JS for the indeterminate (mixed) state.

Notes

• Styled with appearance: none and a custom checkmark via ::after pseudo-element.

• The checkmark uses a CSS-only approach — no SVG or icon font needed.

• Indeterminate state is set via JavaScript: checkbox.indeterminate = true;.

• In forced-colors: active, the checkbox reverts to appearance: auto so Windows High Contrast Mode controls rendering.

Default

Basic checkbox with label.

<input class="checkbox" type="checkbox" id="terms">
<label for="terms">Accept terms and conditions</label>

With description

Checkbox with helper text.

You can enable or disable notifications at any time.

<input class="checkbox" type="checkbox" id="notify">
<div>
  <label for="notify">Enable notifications</label>
  <p class="field-description">...</p>
</div>

Disabled

<input class="checkbox" type="checkbox" disabled>
<input class="checkbox" type="checkbox" disabled checked>

Checked by default

<input class="checkbox" type="checkbox" id="option" checked>
<label for="option">Pre-checked option</label>

Indeterminate

Set via JavaScript: checkbox.indeterminate = true.

<input class="checkbox" type="checkbox" id="select-all">
<label for="select-all">Select all</label>

<script>
  document.getElementById('select-all').indeterminate = true;
</script>

Invalid

Shows destructive border via aria-invalid="true".

<input class="checkbox" type="checkbox" aria-invalid="true">
<label for="terms">Accept terms and conditions</label>

Group

Multiple checkboxes in a group using <fieldset> and <legend>.

Select items to display on the desktop:

Choose which items are visible.

<fieldset>
  <legend>Select items to display on the desktop:</legend>
  <p class="field-description">Choose which items are visible.</p>
  <div class="checkbox-item">
    <input class="checkbox" type="checkbox" id="item-1" checked>
    <label for="item-1">Hard disks</label>
  </div>
  <div class="checkbox-item">
    <input class="checkbox" type="checkbox" id="item-2" checked>
    <label for="item-2">External disks</label>
  </div>
  <!-- ... more items -->
</fieldset>

CSS view file

/* -- Checkbox component ----------------------------------------- */

@layer components {
  .checkbox {
    appearance: none;
    width: 1.125rem;
    height: 1.125rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--background);
    cursor: pointer;
    flex-shrink: 0;
    position: relative;
    transition: background-color 150ms, border-color 150ms;

    &:checked {
      background-color: var(--primary);
      border-color: var(--primary);

      &::after {
        content: '';
        position: absolute;
        left: 50%;
        top: 45%;
        width: 6px;
        height: 10px;
        border: solid var(--primary-foreground);
        border-width: 0 2px 2px 0;
        transform: translate(-50%, -50%) rotate(45deg);
      }
    }

    &:indeterminate {
      background-color: var(--primary);
      border-color: var(--primary);

      &::after {
        content: '';
        position: absolute;
        left: 50%;
        top: 50%;
        width: 10px;
        height: 2px;
        background: var(--primary-foreground);
        transform: translate(-50%, -50%);
      }
    }

    &:focus-visible {
      outline: 2px solid var(--ring);
      outline-offset: 2px;
    }

    &:disabled {
      opacity: 0.5;
      cursor: not-allowed;
    }

    &:is([aria-invalid="true"], :user-invalid) {
      border-color: var(--destructive);
    }
  }

  /* -- Checkbox item layout --------------------------------- */
  .checkbox-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;

    & > label {
      font-size: 0.875rem;
      cursor: pointer;
    }
  }

  .checkbox-item-block {
    display: flex;
    align-items: flex-start;
    gap: 0.5rem;

    & > label {
      font-size: 0.875rem;
      cursor: pointer;
    }

    & > .checkbox {
      margin-top: 0.125rem;
    }
  }

  /* Disabled auto-styling */
  .checkbox-item:has(.checkbox:disabled),
  .checkbox-item-block:has(.checkbox:disabled) {
    opacity: 0.5;
    cursor: not-allowed;
  }

  /* -- Accessibility ---------------------------------------- */
  @media (prefers-reduced-motion: reduce) {
    .checkbox {
      transition: none;
    }
  }

  @media (prefers-contrast: more) {
    .checkbox {
      border-width: 2px;
    }

    .checkbox:disabled {
      opacity: 0.7;
    }
  }

  @media (forced-colors: active) {
    .checkbox {
      appearance: auto;
    }
  }
}