| WatchOS 11 | Apple Inc. | 2024 | — |
| WatchOS 2 | Apple Inc. | 2015 | Apple Public Source License |
| WatchOS 26 | — | — | — |
| WatchOS 3 | Apple Inc. | 2016 | Apple Public Source License |
| WatchOS 4 | — | 2017 | Apple Public Source License |
| WatchOS 5 | — | 2018 | Apple Public Source License |
| WatchOS 6 | Apple Inc. | — | — |
| WatchOS 7 | Apple Inc. | — | — |
| WatchOS 8 | Apple Inc. | — | — |
| WatchOS 9 | Apple Inc. | — | — |
| WattOS | — | — | — |
| Wear OS | Google | 2014 | Apache License |
| Webconverger | — | — | — |
| WebOS | LG Electronics | — | GNU General Public License, Apache License |
| WebOS Open Source Edition | — | — | Apache Software License 2.0 |
| WEGA | EAW | — | — |
| What's Your Sign? | Objective-See | — | GNU General Public License, version 3.0 |
| White Box Enterprise Linux | — | — | GNU General Public License |
| Whitix | — | — | — |
| Whonix | — | 2012 | GNU General Public License |
| Wienux | — | — | — |
| Wifislax | — | — | — |
| Wifiway | — | — | — |
| Wii system software | Nintendo | 2006 | — |
| Wii U system software | Nintendo | — | — |
| Wind River Linux | — | — | — |
| WindexOS | — | — | — |
| Windows 1.0 | Microsoft, NEC | 1985 | end-user license agreement |
| Windows 1.04 | Microsoft | 1987 | — |
| Windows 10 | Microsoft | 2015 | shareware, Microsoft Software Assurance, Azure Dev Tools for Teaching |
| Windows 10 Home | Microsoft | — | — |
| Windows 10 IoT | Microsoft | — | — |
| Windows 10 S | Microsoft | — | — |
| Windows 10 Version 1507 | Microsoft | 2015 | — |
| Windows 10 Version 1511 | Microsoft | 2015 | — |
| Windows 10 Version 1607 | Microsoft | — | — |
| Windows 10 Version 1703 | Microsoft | — | — |
| Windows 10 Version 1709 | Microsoft | 2017 | — |
| Windows 10 Version 1803 | Microsoft | — | — |
| Windows 10 Version 1809 | Microsoft | 2018 | — |
| Windows 10 Version 1903 | Microsoft | 2019 | — |
| Windows 10 Version 1909 | Microsoft | — | — |
| Windows 10, version 20H2 | Microsoft | — | — |
| Windows 10, version 21H1 | Microsoft | 2021 | — |
| Windows 10, version 21H2 | Microsoft | 2021 | — |
| Windows 10, version 22H2 | Microsoft | 2022 | — |
| Windows 10X | Microsoft | — | — |
| Windows 11 | Microsoft | 2021 | end-user license agreement |