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.

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.

Feel free to build your forms however you like, with <fieldset>s, <div>s, or nearly any other element.

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.

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.

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.

As shown in the previous examples, our grid system allows you to place any number of .cols within a .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 .cols equally split the rest, with specific column classes like .col-sm-7.

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.

Use the .row-cols-* classes to create responsive horizontal layouts. By adding gutter modifier classes, we’ll have gutters in horizontal and vertical directions. On narrow mobile viewports, the .col-12 helps stack the form controls and more. The .align-items-center aligns the form elements to the middle, making the .form-checkbox align properly.