The tool
Where to look
- Windows: open Word or Excel → File → Account. The product name is under "Product Information"; the version and build are under "About Word" (click the button to see the full line).
- Mac: open Word → Word menu → About Microsoft Word. The dialog shows the version, build and licence type.
- No Office app installed? Then there is nothing to check — see which Office edition fits.
Build numbers explained
Every Office release since 2016 reports a major version of 16.0, which is why "Version 16" tells you nothing on its own. The build number does: perpetual releases ship from fixed build ranges, while Microsoft 365 moves to a new build every month.
| Release | Build range (16.0.x) | Support ends |
|---|---|---|
| Office 2016 | 4200–4299 at release, patched upward | October 14, 2025 |
| Office 2019 | 10300–10399 at release | October 14, 2025 |
| Office 2021 / LTSC 2021 | 14300–14399 at release | October 13, 2026 |
| Office 2024 / LTSC 2024 | 17900–17999 at release | October 9, 2029 |
| Microsoft 365 | Changes monthly (Current Channel) | While subscribed |
Because perpetual versions receive security patches that raise the build within the release's range, the tool matches on the range rather than an exact number. If your build falls outside every range, you are on Microsoft 365.
What to do next
- On Office 2024 or Microsoft 365: nothing. You are current.
- On Office 2021: you have until October 2026. Plan, don't panic.
- On Office 2019 or older: the apps still open, but no more security fixes. Office Home 2024 or Home & Business 2024 installs over the top and opens all your files.
- Unlicensed: sign in with the right Microsoft account first — activation help walks through it.