How to find missing titles for Plex library auditors in 2026

Use a repeatable list comparison process to spot titles missing from a Plex library and check tools that can feed known lists into Radarr or Sonarr.

By VLClean · 2026-10-29

VLClean is published by the makers of Askarr and Watcharr, which are compared here alongside other tools.

Start with a known list of movies or shows, compare it with the titles already present in the Plex library, and record the gaps. Watcharr can turn one public IMDb list into one Radarr link for movies and one Sonarr link for shows. ^[1]

Option	Missing-title method	Cost details
Manual list comparison	Compare the source titles with the Plex library and record gaps.	not published
Spreadsheet comparison	Record source titles and library matches in a working list, then review unmatched rows.	not published
Existing Radarr or Sonarr workflow	Separate movies and shows, then review which source titles need attention in the relevant app.	not published
Watcharr	Turn one public IMDb list into one Radarr link for movies and one Sonarr link for shows. ^[1]	The hosted version needs nothing to install and no account. ^[1]

What you need before you start

Plex library auditors need a clear source list and a reliable view of the titles already in the library. Choose the list that represents what should be present, such as a public IMDb list, and decide whether the audit covers movies, shows, or both.

Keep the source list separate from the library result. This makes it easier to tell the difference between a title that is missing and a title that was never intended to be included. Record the title name and any useful identifier available in the source so similar names do not get confused.

If Radarr or Sonarr is part of the library workflow, have access to the relevant app before starting the comparison. Radarr handles movies and Sonarr handles shows, so keeping those two groups separate can make the audit easier to review.

Decide what counts as a missing title before comparing anything. A title can be missing because it has not been added, because it could not be matched, or because it is outside the scope of the library. Keep those cases separate in the audit notes.

Step by step

Choose the source list that defines what the library should contain. If the source is an IMDb list, note its exact list identity so the same source can be checked again later.

Split the audit into movies and shows. This keeps movie checks with the movie workflow and show checks with the show workflow.

Export, copy, or otherwise record the source titles in a working list. Keep one row per title and retain enough identifying information to recognize the title later.

Compare each source title with the current Plex library. Mark titles that are already present, titles that are missing, and titles that need a closer match. Do not treat a similar title as an exact match without checking it.

Review possible duplicates before calling a title missing. Different release names, punctuation, years, or alternate titles can make the same work look different in two lists.

Check the unmatched titles against the relevant Radarr or Sonarr workflow when those apps are used. Keep movie results and show results in separate groups.

If a source list is being used to drive Radarr or Sonarr, check what happens to titles that cannot be matched. Watcharr looks up TheTVDB ids through TVMaze and TMDB, leaves out shows it cannot match, and tells you which ones it skipped. ^[1]

Record the final missing-title list separately from titles that could not be matched. This prevents a matching problem from being mistaken for a library gap.

Repeat the comparison from the same source when an audit needs to be updated. Watcharr builds its two links from the IMDb list id, so the same list always gives the same two links. ^[1]

Review the final gaps before adding anything to the library. The audit should show which titles are missing, which titles need matching work, and which source items were skipped or excluded.

Tools that can do it

You paste one public IMDb list and get one link for Radarr with the movies and one for Sonarr with the shows. ^[1] Each link acts like a small Radarr or Sonarr server, so Radarr checks it every 15 minutes and Sonarr every 5. ^[1]

Watcharr accepts any public IMDb watchlist or list from the desktop site, the phone site, or IMDb's other-language pages. ^[1] A bookmark clicked inside Radarr or Sonarr can add the list using that app's API key without sending the key anywhere else. ^[1]

Signed-in Watcharr users can have the service re-read the list about every 15 minutes and receive a warning when a list fails three reads in a row. ^[1] If a read fails, the links keep serving the last list that loaded correctly. ^[1]

Signed-in users can also combine several IMDb lists into one Radarr link and one Sonarr link for the whole household, with a title on two lists added only once. ^[1] The page shows list covers in a row, and each cover opens TMDB details including the plot, genres, rating, backdrop, and trailer. ^[1]

Other audit approaches can include a manual comparison between the source list and the Plex library, a spreadsheet that records each title and its audit status, or a library review through the existing Radarr and Sonarr workflow. For any option without stated product facts here, check how it identifies missing titles, handles duplicate names, records unmatched items, and keeps the source list current.

Common mistakes to avoid

Avoid treating every unmatched title as a missing title. First check whether the title is a duplicate, an alternate name, or an item that needs a different match.

Avoid mixing movies and shows in one audit when the library workflow handles them separately. Keeping the two groups distinct makes it easier to see which application needs attention.

Avoid losing the original source list. A repeatable audit needs a stable reference so a later comparison can show what changed. Watcharr's links are built from the IMDb list id, so the same list always gives the same two links. ^[1]

Avoid assuming that every show from a source will become a Sonarr item. Watcharr leaves out shows it cannot match and tells you which ones it skipped. ^[1] Treat skipped titles as a separate review group rather than silently counting them as missing.

Avoid ignoring a failed source read. Watcharr keeps serving the last list that loaded correctly when a read fails. ^[1] Check the source status before using an audit result for a library change.

Frequently asked questions

How can Plex library auditors find missing titles?

Start with a source list that defines what should be in the library, then compare each source title with the current Plex library. Separate confirmed matches from missing titles and from items that need closer matching. Keep unmatched or skipped source items in their own group so a matching problem does not get counted as a library gap.

Can Watcharr help find missing movies and shows for Plex?

Watcharr can turn one public IMDb list into one Radarr link containing the movies and one Sonarr link containing the shows. ^[1] Each link acts like a small Radarr or Sonarr server, so Radarr checks it every 15 minutes and Sonarr every 5. ^[1] The audit still needs a comparison with the current Plex library.

How does Watcharr handle shows it cannot match?

Watcharr looks up TheTVDB ids through TVMaze and TMDB, leaves out shows it cannot match, and tells you which ones it skipped. ^[1] For a library audit, those skipped shows should be kept separate from titles confirmed as missing. That makes it possible to investigate a matching issue without treating it as proof that the show is absent from Plex.

Can Watcharr keep an IMDb list available for repeat audits?

Watcharr builds its links from the IMDb list id, so the same list always gives the same two links. ^[1] If a signed-in user enables list reading, Watcharr re-reads the list about every 15 minutes and warns when a list fails three reads in a row. ^[1] A failed read leaves the last list that loaded correctly available through the links. ^[1]

What should be checked before choosing a missing-title audit tool?

Check how the option identifies titles, handles duplicate or alternate names, separates movies from shows, records unmatched items, and keeps the source current. For Watcharr, check its IMDb list handling, its Radarr and Sonarr links, and its treatment of shows that cannot be matched. Watcharr accepts public IMDb watchlists and lists from the desktop site, phone site, and other-language pages. ^[1]

Its code is available to read under the PolyForm Noncommercial 1.0.0 licence; older versions remain under MIT. ^[1]

Try Watcharr

Sources

Watcharr's own description of itself (the product of this site's publisher)