WhichDist

Download & install

WhichDist runs on Excel 2016, 2019, 2021, 2024 and Microsoft 365 (Windows & Mac) and Excel on the web. No coding needed — you install one small file (manifest.xml) and Excel does the rest.

Note: Excel 2013 and 2010 are not supported — Microsoft's web add-in platform (Office.js) requires Excel 2016 or later.

Install from the Insert tab — not File → Options. WhichDist is a modern Excel Add-in, so you add it via Insert → Add-ins (browse to manifest.xml). The old File → Options → Add-ins → “Manage: Excel Add-ins” → Browse dialog only accepts legacy .xlam/.xll files and will not load WhichDist.

Step 1 · Download WhichDist (manifest.xml)

Step 2 · Which Excel are you using?

Excel on the web — easiest

  1. Open your workbook at excel.office.com.
  2. Insert → Add-ins → My Add-ins → Upload My Add-in.
  3. Click Browse…, choose manifest.xml, then Upload.
  4. A WhichDist button appears on the Home tab. Select your numbers → Analyze selection.

Windows · Microsoft 365 / recent builds

  1. Insert tab → Add-ins (or More Add-ins).
  2. Open the My Add-ins tab, then click Upload My Add-in (top-right).
  3. Browse… to manifest.xml → Upload. WhichDist appears on the Home tab.

No Upload My Add-in button? You have a perpetual build — switch to the “Windows · 2021 / 2019 / 2016” option above.

Windows · Office 2021 / 2019 / 2016 (perpetual)

No “Upload My Add-in” button — that’s expected. Perpetual builds (incl. Professional Plus 2021) don’t show it; that button ships mainly with Microsoft 365 and Excel on the web. Use the Shared Folder catalog below — the Microsoft-supported route for these builds.
  1. Put manifest.xml in a folder, e.g. C:\WhichDist.
  2. Share the folder: right-click → Properties → Sharing → Share. You need the network path, e.g. \\YOUR-PC\WhichDist — a local C:\… path will not work; it must be a \\ share.
  3. Excel → File → Options → Trust Center → Trust Center Settings → Trusted Add-in Catalogs. Paste \\YOUR-PC\WhichDist, click Add catalog, tick Show in Menu, OK twice.
  4. Fully close and reopen Excel.
  5. Insert → My Add-ins (dropdown arrow) → SHARED FOLDER tab → WhichDist → Add.

Trips people up: it must be a \\ UNC path (not local C:\), you must tick Show in Menu, and you must restart Excel before the Shared Folder tab lists anything.

“Add catalog” does nothing / folder rejected?

  1. Confirm the folder is shared: right-click → Properties → Sharing should show a \\… path. If “Not Shared”, click Share and add Everyone with Read.
  2. Paste that exact \\Computer\Share value (copy it from the Sharing tab), then Add catalog.
  3. Still empty after restart? Make sure manifest.xml is actually inside the shared folder.

Faster — register with a .reg file

Save as whichdist-catalog.reg, set Url to your share path (keep the doubled back-slashes), double-click, restart Excel: 

Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\WEF\TrustedCatalogs\{b8e9c2a1-4f6d-4a2b-9c3e-1a2b3c4d5e6f}]
"Id"="{b8e9c2a1-4f6d-4a2b-9c3e-1a2b3c4d5e6f}"
"Url"="\\\\YOUR-PC\\WhichDist"
"Flags"=dword:00000001
Rather not deal with this? Open excel.office.com with a free Microsoft account and use Upload My Add-in — same add-in, no sharing, Trust Center, or registry.

Excel for Mac

  1. Copy manifest.xml into ~/Library/Containers/com.microsoft.Excel/Data/Documents/wef (create wef if needed).
  2. Restart Excel → Insert → My Add-ins → WhichDist.
Use Google Sheets? WhichDist is a Microsoft Office add-in (Office.js), so it doesn’t install in Google Sheets. Use it free in Excel on the web (excel.office.com) with a free Microsoft account instead. A native Google Sheets version isn’t available yet.

Instructors: push WhichDist to a whole class with nothing for students to install via Microsoft 365 Admin Center → Integrated apps (Centralized Deployment), or install from Microsoft AppSource once listed.

Developer sideload (from source)

Run the task pane locally over HTTPS, then sideload the manifest: 

pnpm install
pnpm --filter @whichdist/stats-engine build
pnpm --filter @whichdist/excel-addin dev   # serves https://localhost:3000

# Then sideload apps/excel-addin/manifest.xml:
#   Windows: share a folder as a trusted catalog, or use
#            npx office-addin-debugging start apps/excel-addin/manifest.xml
#   Mac:     copy manifest.xml to ~/Library/Containers/com.microsoft.Excel/
#            Data/Documents/wef
#   Web:     Insert → Add-ins → Upload My Add-in → manifest.xml