When to use
Buttons use a variety of sizes, colors, and iconography combinations.
Use a Button to enable actions or decisions that are important to a user. They should be used throughout your UI, it can be used in situations where users need to :
submit a form,
confirm a change,
trigger a new element to appear on the page,
specify a new or next step in a process.
Button is used for actions, like ‘Load more’, ‘Filters’ etc.
Links for links.
When not to use
Do not use buttons as navigational elements. Instead, use links when the desired action is to take the user to a new page (with the exception of the back and forward buttons).
Do not use Links for actions, only for links.
Do not style Buttons as links.
Do not use two icons at the same time.
Writing labels
Do
Button labels use sentence case (Capitalize the first letter, use lowercase for everything else) and are as short as possible
Don’t
Use label while clearly explaining what happens when the button is activated.
The button text should be actionable so users know exactly what to expect when clicking.
Do
Button labels are as short as possible, while clearly explaining what happens when the button is activated.
Don’t
For maximum legibility, a text label should remain on a single line. Find another label if you can’t do it !
Combining button styles
Do
When using multiple buttons, you can place an outlined primary button next to a primary button.
Don’t
Avoid using two primary buttons next to one another.
Do
If you really need to use two similar buttons you can use secondary buttons.
Do
The primary button should only be used once per view.
Don’t
Use several primary buttons it will loose emphasis.
Stretched buttons on mobile
Do
Keep mobile margin with stretched button on mobile.
Don’t
Use full screen with stretched button on mobile.
Alignment
Button alignment by default should be start-aligned. However, buttons can appear center-aligned or end-aligned if required. Alignment depends on regional specific text direction.
Disabled/inactive Buttons
Inactive buttons can be used to communicate to the user that a certain action would be possible if circumstances were different.
Reduce opacity, not hue saturation.
Put it next to enabled buttons when it's possible.
Use “cursor disabled” on desktops on hover state.
Add supporting text.