Autocomplete

Suggest options as users type

What it solves

Autocomplete helps users quickly find and select values from predefined options as they type. Autocomplete combines text input flexibility with dropdown-style selection, providing real-time suggestions matching user input. This pattern reduces errors, speeds data entry, and improves form completion.

When to use

• Users select from large sets of predefined options (country selection, airport codes)
• Users need faster option selection than scrolling through long dropdowns
• Reducing errors by guiding users to valid input options
• Input has finite, known valid responses
• Combining free text input with suggestion functionality

When to avoid

• Fewer than 10 options exist (use standard dropdown/select instead)
• Users enter completely free-form text without restrictions
• All options need simultaneous visibility for comparison
• Network latency significantly delays suggestion results
• Input field requires exact, verbatim text entry (passwords)

Implementation workflow

1. Confirm the pattern matches the problem and constraints before copying the example.
2. Start from the anatomy and examples in references/pattern.md, then choose the smallest viable variation.
3. Apply accessibility, performance, and interaction guardrails before layering visual polish.
4. Use the testing guidance to verify behavior across keyboard, screen reader, responsive, and failure scenarios.

Accessibility guardrails

• Ensure the input is labeled and announced as a combobox (role="combobox", aria-expanded, aria-controls).
• Support full keyboard interaction: ArrowUp/ArrowDown, Enter, Escape, and Tab.
• Expose active option context with aria-activedescendant and stable option IDs.
• Announce loading, empty, and error states to screen readers.
• Keep suggestions readable with strong contrast and visible focus styles.

Related patterns

• https://uxpatterns.dev/patterns/autocomplete/do-dont-accessibility-1
• https://uxpatterns.dev/patterns/autocomplete/do-dont-content-1
• https://uxpatterns.dev/patterns/autocomplete/do-dont-visual-design-2
• https://uxpatterns.dev/patterns/forms/date-picker
• https://uxpatterns.dev/patterns/forms/multi-select-input
• https://uxpatterns.dev/patterns/forms/text-field

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For full implementation detail, examples, and testing notes, see references/pattern.md.

Pattern page: https://uxpatterns.dev/patterns/forms/autocomplete