The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- WebDB (7 members)
- Webmail (1 member)
- Website (1 member)
- Websites (17 members)
- West End (1 member)
- Western Australia (1 member)
- Wget (1 member)
- Wheelbarrow (1 member)
- White Gum Valley (1 member)
- Why I write (1 member)
- WikiClubWest (1 member)
- Wiki Wednesday (1 member)
- Wikidata (3 members)
- Wikimania (1 member)
- Wikimedia (32 members)
- Wikimedia Australia (1 member)
- Wikimedia Commons (0 members)
- Wikipedia (8 members)
- Wikis (15 members)
- Wikisource (23 members)
- Wikiteam (1 member)
- Wiktionary (2 members)
- William Morris (1 member)
- Windows (3 members)
- Windows Key (1 member)
- Winterfold Road (1 member)
- Women's Auxiliary Australian Air Force (1 member)
- Wood (2 members)
- Woodwork (6 members)
- Woodwork technique (1 member)
- Woodworking (39 members)
- Wordpress (23 members)
- Wordpress plugins (1 member)
- Words (4 members)
- Wordsworth (1 member)
- Work (24 members)
- Workbench (1 member)
- Workflow (1 member)
- Working from home (1 member)
- Workshop (2 members)
- World Wide Web (1 member)
- World wide web (10 members)
- Writing (18 members)
- Writing in public view (3 members)
- X220 (1 member)
- Xorg.conf (1 member)
- YouTube (3 members)
- Young greens (1 member)
- Z-order (curve) (1 member)
- Zend (1 member)