| wsk | Ashampoo Media Player Skin |
| wskn | Wise Care 365 Skin Data |
| wsl | Win-Situ Log |
| wsml | Web Service Modeling Language Data |
| wspak | WebsitePanel Backup |
| wspfile | Microsoft SharePoint Solution Data |
| wsr | Mail.dat Walk Sequence File |
| wsstyles | Windows Sidebar Styler Style |
| wsv | SpectraMagic v3.6 Data |
| wsvs | Wondershare Filmora Data |
| wsw | WebSite-Watcher Bookmark List |
| wsx | WinMX Server Information File |
| wsxz | SDL WorldServer WSXZ Package |
| wsz | WinAMP Skin |
| wt | WiredTiger Database Dump |
| wt4 | Win-Test Binary Log |
| wta | Tennis Navigator WTA Data File |
| wtb | Win-Test Binary Log |
| wtc | Wikitude Studio Image Collection Data |
| wtf | WaveThunder Factory Data |
| wtf | WinTaper Data File |
| wtfav | Watchtower Library Favourites Data |
| wtg | WAsP Wind Turbine Generator Data |
| wth | CONTAM Weather Data |
| wtk | WinTalk URL |
| wtl | Windows Test Technologies Logger Results |
| wtm | WaveThunder Music Data |
| wtml | WorldWide Telescope Collection Data |
| wto | Wikitude Studio Object |
| wtpl | WireTap Studio Library |
| wtr | FARSITE Weather Data |
| wtr | SimSig WTT Timetable Rules |
| wts | WebPlus Theme Set |
| wtt | SimSig WTT Timetable |
| wtw | WaveThunder WAV Shadow Data |