What I Already Own vs LibraryThing: which app to catalog your books?
LibraryThing is an online book catalog, free with no limit since 2020, drawing on records from many libraries. What I Already Own is a paid app built for the phone: scanning of the exact edition, what your series are missing, and an answer even without a signal.
Facts current as of September 29, 2026, taken from the publishers’ official pages, numbered and dated at the bottom of the page.
Scanning is free. At your first add: 7-day trial at €0, card required, then €3.95 a month or €39.95 a year, cancel anytime. Your collection stays exportable.
In short
Stay with LibraryThing if a free, unlimited catalog is enough for you, especially from a computer, and if library records matter to you. Go with What I Already Own if you mostly catalog on your phone, in a bookstore or at a flea market, if you want to know what your series are missing, and if you also collect records.
Side by side
| Criterion | What I Already Own | LibraryThing |
|---|---|---|
| Price | What I Already Own€3.95 a month or €39.95 a year, tax included, after a 7-day trial. Books and records included. | LibraryThingFree with no limit on books since March 2020, with no ads for members. 1 |
| Platforms | What I Already OwnAn app that installs on iPhone and Android from the browser, without the App Store or Google Play. On a computer, in the browser. | LibraryThingWebsite; iOS app last updated in February 2024, Android app in January 2025. 2 3 |
| Barcode scanning | What I Already OwnWith the camera; when one barcode covers several editions, you pick yours. No barcode? Search by title. | LibraryThingISBN with the camera, in the apps; search by title. 2 3 |
| What you can catalog | What I Already OwnBooks and records (vinyl, CDs, cassettes). | LibraryThingMostly books; also DVDs and CDs. 3 |
| Where the data comes from | What I Already OwnOpen Library, the French National Library (BnF), the national libraries of Spain, Japan and Taiwan, Wikidata; MusicBrainz and Discogs for records. Sources and licenses are published. | LibraryThingAmazon and more than 65 million library records, from more than 1,000 sources to choose from. 2 3 |
| Market value | What I Already OwnNo market value shown at this time. You can record the price paid and the selling price. | LibraryThingNo market value mentioned. 2 3 |
| Offline | What I Already OwnThe app knows without a signal whether you already own a book; scans made offline are processed once you’re back online. | LibraryThingNo offline mode mentioned in the app descriptions. 2 3 |
| Export | What I Already OwnCSV file, plus an inventory you can print or save as a PDF. | LibraryThingCSV, TSV or Excel. 4 |
| Import | What I Already OwnExports from Discogs, CLZ and Libib, and any spreadsheet with a title and an ISBN or barcode. | LibraryThingImports a Goodreads library, with ratings, reviews, and shelves turned into tags. 5 |
| Languages | What I Already OwnEnglish, French, German, Italian, Spanish and Japanese. | LibraryThingiOS app in English. 2 |
What LibraryThing does better
- It’s free. As many books as you like, without paying anything and with no ads. 1
- Library records. More than 1,000 sources to choose from to describe your books, with more than 65 million records. 2 3
- Export. CSV, TSV or Excel: your data goes wherever you want. 4
- Libraries. Its publisher also offers TinyCat, a catalog for small libraries. 1
How What I Already Own is different
- An app built for the phone. It installs on iPhone and Android from the browser, and every update reaches every device at the same time.
- The exact edition. When one barcode covers several editions, you pick yours; for a record, the pressing, country and label.
- An answer without a signal. In a used bookstore or at a flea market, the scan tells you whether the book is already on your shelf, even with no connection.
- What your series are missing. For every series and every author you’ve started, the app lists the volumes and books you don’t have yet.
- Records with the same care: vinyl, CDs and cassettes, identified down to the pressing.
Scanning is free. At your first add: 7-day trial at €0, card required, then €3.95 a month or €39.95 a year, cancel anytime. Your collection stays exportable.
Frequently asked questions
- LibraryThing is free. Why pay for What I Already Own?
- If an online catalog is all you need, LibraryThing is a very good choice, free and unlimited. What I Already Own is worth paying for on your phone: scanning of the exact edition, an answer without a signal in a bookstore or at a flea market, the volumes your series are missing, and your records alongside your books.
- Can I bring over my LibraryThing catalog?
- Yes, by file: export it as CSV from LibraryThing, then drop it into What I Already Own (Settings, Import a collection). Every book with an ISBN is found; the others are listed separately.
- Are the LibraryThing apps up to date?
- According to the app stores, the iOS app was last updated in February 2024, and the Android app in January 2025. What I Already Own is an installable web app: the same version on iPhone, Android and computer.
- Does LibraryThing tell me what my books are worth?
- Its description mentions no market value. What I Already Own does not show one today either; you can record the price you paid.
- What about a school or community library?
- Look at TinyCat, the catalog for small libraries from the publisher of LibraryThing, or at Libib. What I Already Own is built for a personal collection.
The catalog, no account needed
The lists What I Already Own keeps up to date for you: discographies, bibliographies and reading orders.
Sources
The publishers’ official pages, with the date we checked each one. Prices and plans change: confirm them with the publisher before you subscribe.
- 1LibraryThing blog, LibraryThing goes freehttps://blog.librarything.com/2020/03/librarything-goes-free/Checked on September 29, 2026.
- 2LibraryThing, App Storehttps://apps.apple.com/us/app/librarything/id948824489Checked on September 29, 2026.
- 3LibraryThing, Google Playhttps://play.google.com/store/apps/details?id=com.librarything.librarythingChecked on September 29, 2026.
- 4LibraryThing blog, Excel exporthttps://blog.librarything.com/2016/08/new-feature-true-excel-export/Checked on September 29, 2026.
- 5LibraryThing blog, Sync your Goodreads to LibraryThinghttps://blog.librarything.com/2013/05/sync-your-goodreads-to-librarything/Checked on September 29, 2026.
This page is published by What I Already Own, one of the apps compared. We review it every three months. Spotted an error or a fact that has changed? Write to us at [email protected].