Best Practices for Designing UI Buttons

Carefully consider the padding you use around a button’s label. Leave enough room so that the text won’t look like sardines in a can.

A good rule of thumb is to make the padding on the width twice as much as the padding on the height of the button. At minimum, an uppercase “W” should fit between the label and the edge of the button.^[1]

On the web, a button's width usually adjusts according to its label.

Color is a powerful tool in design that instantly communicates meaning. Utilizing it as a visual signifier can guide users' attention to key elements like buttons. For instance, the color red is often associated with alerts or destructive actions. It serves as a clear signal for features such as error messages or delete functions.

By aligning color cues with user expectations, you create a more intuitive interface that helps users navigate more effortlessly. Just remember, the colors should complement the overall design and meet accessibility standards for optimal user experience.

Consistency is key. Stick to one style for buttons throughout your product. Inconsistent designs confuse users and add more mental load to using your product. Consistency can be achieved through things like a single color palette, icon style, typography, and similar design choices.

Button hierarchy is crucial in defining the user flow in an interface. Always differentiate between primary, secondary, and even tertiary buttons based on their level of importance.

The primary button, often used for actions like "Submit" or "Next," should be the most visually prominent. Secondary and tertiary buttons, like "Cancel" or "Back," should be less eye-catching but still easily identifiable.

Utilize varying shades, sizes, or subtle effects like shadows to distinguish these buttons. A well-executed button hierarchy not only eases cognitive load but also makes user interaction more intuitive and efficient. Failing to establish a clear hierarchy could lead to user confusion or errors, disrupting the overall user experience.

While it's fun to let your creativity flow, it's essential to exercise caution when it comes to button design. The key is balance. You want your buttons to both catch the eye and serve their function seamlessly.

3 golden rules to keep in mind:

• Make sure it looks like a button: Users should instantly recognize it as something they can interact with.
• Keep it readable: No matter how stylish your font or how unique your color scheme is, users must be able to quickly read the label.
• Stick to conventions: Creative colors, shapes, and fonts are okay in moderation, but going too far off the beaten path can lead to user confusion.

Feel free to push boundaries, but always prioritize user experience and usability over aesthetic experiments.

Ensuring your buttons are easily visible isn't just good design—it's an accessibility imperative. From an accessibility standpoint, the contrast between the button and its background needs to meet the Web Content Accessibility Guidelines (WCAG). This ensures that everyone, including those with vision impairments, can interact with your interface.

Here are some tips:

• Aim for a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text.
• Use tools to check your contrast ratio; don't just trust your eyes.
• If your button is on a complex background like an image, consider adding a semi-opaque background to boost contrast.

Remember, high contrast isn't just about readability; it's about making your design inclusive for all users.

Soft shadows, when used properly, can be an excellent way to create visual interest in a design and make certain elements stand out. But when designing transparent buttons or for button labels, it’s best to avoid shadows as they can make the label entirely unreadable if used in excess.

If you decide to make all buttons grow with their label, consider defining a minimum width. Overly narrow buttons may fail to reach the accessible touch/click target area size, seem disproportionate, lose emphasis, or may even fail to look like buttons.

Size is one of the most important aspects of button design. It is closely tied to conversion rates, the number of errors users make, and overall usability. When designing for mobile devices, you’ll want to keep the size of users’ fingers in mind when determining the button height of your buttons.

According to MIT Touch Lab studies, the minimum touch target size is 16-20mm (~45-57px) which equals the average adult person's fingertip size. Notably, the impact area of an average adult's thumb is even larger — 25x25mm (72px).^[2]

On desktop interfaces, you’ll want to provide enough top and bottom padding within your button to keep the label legible and provide plenty of area for users to click to increase accessibility.

A button's label font size should be large enough to notice and scan. The ideal size varies across device, platform, and typeface, but 16px is the minimum recommended size for body text. Text smaller than that can be uncomfortable for users to read and make them strain their eyes.

While it's common to let buttons scale with their content, setting a fixed width is a valuable alternative. This tactic shines in mobile interfaces where you often find primary and secondary buttons stacked vertically. By using a fixed width for both, you create a balanced, easy-to-navigate space that looks good and feels intuitive. Uniform sizing not only standardizes visual elements across your interface but also enhances the user experience by removing guesswork.