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Avoid using primary buttons for less important actions, see Guidelines on secondary buttons and Guidelines on tertiary buttons
Don’t use primary buttons for destructive and irreversible actions such as deleting content or canceling a request. See Guideline on destructive buttons
When using buttons for pagination − the "Next" button is considered the primary action button and appears on the right of the page but should still be styled as a secondary button.
Best practices
Do
Label buttons clearly and keep text short yet descriptive. Labels should use a max of 25 characters. Use common action verbs to help users to understand what action they are initiating when they interact with the button
Consider the French translation when designing and placing primary buttons on an interface since French uses approximately 2.2x more characters than English
Use a color that stands out such as a primary branding color to signify importance and capture the users attention. Ensure the is sufficient color contrast between the button and text
Place primary buttons somewhere prominent and at the natural end of a task or action. Try to be consistent with the placement across an application or website
When pairing a primary button with a secondary button, such as in a modal, place the primary button on the right of the secondary button. If designing for mobile, place the primary button above the secondary
Buttons should be the size of the text label with additional padding. Use 32px of horizontal spacing (white space) between buttons for desktop and 24px of vertical spacing (white space) between block-level buttons for mobile
Don’t
Don’t use primary buttons for actions the have minimal impact on or distract from the users main task or goalDon’t hide primary buttons and make them challenging for users to locate
Don’t overuse primary buttons
Don’t use multiple different colors for primary buttons across an application
Don’t underline text on a primary button
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