Choose criteria that support decisions
Observe the questions people ask before choosing. A directory may need category, region and resource type; a catalogue may need availability, size or use. Add a criterion only when the relevant entries carry dependable data.
Define values and synonyms before publishing. Two labels meaning the same thing scatter results. The web directory
- Criteria tied to decisions.
- Reliable data on relevant entries.
- Values and synonyms harmonised.
Show results and state
After a selection, show the result count and active filters. People should be able to remove one criterion or reset all. A no-results state should explain what happened and suggest a reasonable step without silently clearing selections.
Test combinations, browser back, category changes and free-text search. Cards need readable titles and essential information even when images fail. The site-search guide
- Count and criteria visible.
- Simple reset.
- No-results state explained.
Support keyboard and mobile
Checkboxes, selects and buttons need clear labels, logical order and visible focus. If results change without a reload, announce the change without interrupting reading after every keystroke. On mobile, check the filter panel and remaining space for cards.
Test by keyboard, at high zoom and on narrow screens. A mouse-friendly filter can still make removal impossible for a screen reader or phone user. The accessibility guide
- Controls named and reachable.
- Result changes perceptible.
- Mobile panel usable.
Decide which URLs deserve crawling
Some selections may warrant stable, useful pages; most combinations do not need indexable URLs. Document the decision before generating many parameters. Keep individual entries and a complete main listing accessible.
Google guidance on faceted navigation
- Public URLs chosen deliberately.
- Entries reachable without filters.
- Empty and duplicate combinations checked.