* Remove about generated button of file form * Remove and merge layout examples of custom forms * Clarify id/for * Change some spacing classes for consistency
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layout | title | description | group | toc |
---|---|---|---|---|
docs | Layout | Give your forms some structure—from inline to horizontal to custom grid implementations—with our form layout options. | forms | true |
Forms
Every group of form fields should reside in a <form>
element. Bootstrap provides no default styling for the <form>
element, but there are some powerful browser features that are provided by default.
- New to browser forms? Consider reviewing the MDN form docs for an overview and complete list of available attributes.
<button>
s within a<form>
default totype="submit"
, so strive to be specific and always include atype
.- You can disable every form element within a form with the
disabled
attribute on the<form>
.
Since Bootstrap applies display: block
and width: 100%
to almost all our form controls, forms will by default stack vertically. Additional classes can be used to vary this layout on a per-form basis.
Utilities
[Margin utilities]({{< docsref "/utilities/spacing" >}}) are the easiest way to add some structure to forms. They provide basic grouping of labels, controls, optional help text, and form validation messaging. We recommend sticking to margin-bottom
utilities, and using a single direction throughout the form for consistency.
Feel free to build your forms however you like, with <fieldset>
s, <div>
s, or nearly any other element.
{{< example >}}
Form grid
More complex forms can be built using our grid classes. Use these for form layouts that require multiple columns, varied widths, and additional alignment options. Requires the $enable-grid-classes
Sass variable to be enabled (on by default).
{{< example >}}
Form row
You may also swap .row
for .form-row
, a variation of our standard grid row that overrides the default column gutters for tighter and more compact layouts. Also requires the $enable-grid-classes
Sass variable to be enabled (on by default).
{{< example >}}
More complex layouts can also be created with the grid system.
{{< example >}}
Horizontal form
Create horizontal forms with the grid by adding the .row
class to form groups and using the .col-*-*
classes to specify the width of your labels and controls. Be sure to add .col-form-label
to your <label>
s as well so they're vertically centered with their associated form controls.
At times, you maybe need to use margin or padding utilities to create that perfect alignment you need. For example, we've removed the padding-top
on our stacked radio inputs label to better align the text baseline.
{{< example >}}
Horizontal form label sizing
Be sure to use .col-form-label-sm
or .col-form-label-lg
to your <label>
s or <legend>
s to correctly follow the size of .form-control-lg
and .form-control-sm
.
{{< example >}}
Column sizing
As shown in the previous examples, our grid system allows you to place any number of .col
s within a .row
or .form-row
. They'll split the available width equally between them. You may also pick a subset of your columns to take up more or less space, while the remaining .col
s equally split the rest, with specific column classes like .col-7
.
{{< example >}}
Auto-sizing
The example below uses a flexbox utility to vertically center the contents and changes .col
to .col-auto
so that your columns only take up as much space as needed. Put another way, the column sizes itself based on the contents.
{{< example >}}
You can then remix that once again with size-specific column classes.
{{< example >}}
Inline forms
Use the .form-inline
class to display a series of labels, form controls, and buttons on a single horizontal row. Form controls within inline forms vary slightly from their default states.
- Controls are
display: flex
, collapsing any HTML white space and allowing you to provide alignment control with [spacing]({{< docsref "/utilities/spacing" >}}) and [flexbox]({{< docsref "/utilities/flex" >}}) utilities. - Controls and input groups receive
width: auto
to override the Bootstrap defaultwidth: 100%
. - Controls only appear inline in viewports that are at least 576px wide to account for narrow viewports on mobile devices.
You may need to manually address the width and alignment of individual form controls with [spacing utilities]({{< docsref "/utilities/spacing" >}}) (as shown below). Lastly, be sure to always include a <label>
with each form control, even if you need to hide it from non-screenreader visitors with .sr-only
.
{{< example >}}
Choose... One Two Three
Submit
{{< /example >}}{{< callout warning >}}
Alternatives to hidden labels
Assistive technologies such as screen readers will have trouble with your forms if you don't include a label for every input. For these inline forms, you can hide the labels using the .sr-only
class. There are further alternative methods of providing a label for assistive technologies, such as the aria-label
, aria-labelledby
or title
attribute. If none of these are present, assistive technologies may resort to using the placeholder
attribute, if present, but note that use of placeholder
as a replacement for other labelling methods is not advised.
{{< /callout >}}