Plan reusable website components without repeating mistakes

Plan a reusable website component by defining the job it does, the content it can hold and how it behaves in different states. Reuse should make pages clearer and easier to maintain. It becomes a problem when a rigid component forces unrelated content into the same shape.

Start with a repeated need

Look across real pages for patterns: service cards, testimonial blocks, alerts, forms or calls to action. Ask whether they serve the same visitor purpose. Two blocks that look alike may need different rules if one explains a product and another reports a time-sensitive warning.

Choose a small pilot set. A component library built entirely from imagined future pages can become large before it has proved useful. The design-system decision guide helps judge whether a broader system is worth maintaining.

Write a content contract

Record required fields, optional fields and sensible length ranges. For a service card, this might mean a clear title, one-sentence description and a destination label. Decide what happens when an image is missing or a title wraps to three lines. Avoid arbitrary limits that cause editors to remove meaning.

Include examples of good and bad use. A callout component might be suitable for a key condition, but not for every paragraph the editor wants to emphasise. Naming the purpose prevents visual sameness from hiding different jobs.

Cover states and devices

Sketch default, hover, focus, error and empty states where relevant. Test the component with keyboard use, enlarged text and a phone layout. A form field is not complete because its empty state looks polished; it also needs labels, help text and recovery from mistakes.

Check how components interact. Several strong calls to action on one page can compete even if each individual component works. Page-level review remains necessary.

Assign maintenance responsibility

Decide who can change the component, how changes are tested and how existing pages receive fixes. Keep examples and usage notes close to the code or CMS configuration people actually use. A documented component that editors cannot find will drift into one-off versions.

Review the library as real pages change. Retire components that no longer solve a distinct need and allow a justified exception when a page's task differs.

Document an example of appropriate use and a counterexample for each component. A comparison card may suit three equivalent options, but not a list of unrelated services with different decision criteria. These examples help editors choose components for their information needs instead of copying a layout by habit.

Frequently asked questions

Should every repeated block become a component?

No. Reuse is useful when purpose and behaviour repeat. A one-off block may be clearer than a complex component with many exceptions.

How strict should content length limits be?

Set ranges based on real layouts and reading needs, then test longer examples. Do not cut important information simply to preserve equal card heights.

Who should approve a new component?

The people responsible for content, design and development should review its purpose and accessibility. Give one team ownership of the final decision.