Easily extend form controls by adding text, buttons, or button groups on either side of textual `<input>`s.
## Contents
* Will be replaced with the ToC, excluding the "Contents" header
{:toc}
## Basic example
Place one add-on or button on either side of an input. You may also place one on both sides of an input. **We do not support multiple add-ons on a single side, nor multiple form-controls in a single input group.**
<inputtype="text"class="form-control"aria-label="Amount (to the nearest dollar)">
<spanclass="input-group-addon">.00</span>
</div>
{% endexample %}
## Sizing
Add the relative form sizing classes to the `.input-group` itself and contents within will automatically resize—no need for repeating the form control size classes on each element.
Place any checkbox or radio option within an input group's addon instead of text.
{% example html %}
<divclass="row">
<divclass="col-lg-6">
<divclass="input-group">
<spanclass="input-group-addon">
<inputtype="checkbox"aria-label="Checkbox for following text input">
</span>
<inputtype="text"class="form-control"aria-label="Text input with checkbox">
</div>
</div>
<divclass="col-lg-6">
<divclass="input-group">
<spanclass="input-group-addon">
<inputtype="radio"aria-label="Radio button for following text input">
</span>
<inputtype="text"class="form-control"aria-label="Text input with radio button">
</div>
</div>
</div>
{% endexample %}
## Button addons
Buttons in input groups are a bit different and require one extra level of nesting. Instead of `.input-group-addon`, you'll need to use `.input-group-btn` to wrap the buttons. This is required due to default browser styles that cannot be overridden.
Screen readers will have trouble with your forms if you don't include a label for every input. For these input groups, ensure that any additional label or functionality is conveyed to assistive technologies.
The exact technique to be used (`<label>` elements hidden using the `.sr-only` class, or use of the `aria-label`, `aria-labelledby`, `aria-describedby`, `title` or `placeholder` attribute) and what additional information will need to be conveyed will vary depending on the exact type of interface widget you're implementing. The examples in this section provide a few suggested, case-specific approaches.