Is What I Already Own an alternative to CLZ?

For records and books, yes: barcode scanning, the exact edition, your collection on your phone and your computer, export. For comics, movies or video games, no: What I Already Own does not catalog them.

How much does CLZ cost for books and records?

CLZ sells CLZ Books and CLZ Music separately, each with a mobile subscription (€19.95 a year) and a web subscription (€39.95 a year), or both for €49.90 a year. Books and records on your phone and your computer: €99.80 a year, based on prices published on September 28, 2026. What I Already Own: €39.95 a year for everything.

Can I bring over my CLZ collection?

Yes, by file: export your collection as CSV from CLZ Web or CLZ Cloud, with the Barcode (records) or ISBN (books) field, then drop it into What I Already Own (Settings, Import a collection). Every item found joins your collection, with its condition, price and purchase date when the export includes them.

Does CLZ tell me what my collection is worth?

For books, yes: CLZ Books estimates each book's value from the used prices found for its ISBN, regardless of condition. For records, CLZ Music leaves the field for you to fill in. What I Already Own does not show a market value today.

Do I need a credit card to try it?

With What I Already Own, yes: a card is required at the start of the 7-day trial, and nothing is charged if you cancel before it ends. With CLZ, the web trial needs no card; on phones, it runs through your App Store or Google Play account.

What I Already Own

What I Already Own vs CLZ: which one for your records and books?

CLZ sells one app per category and per platform. What I Already Own covers records and books, on your phone and your computer, with a single subscription. Here is what sets them apart, fact by fact, with sources.

Facts checked on September 28, 2026 on the publishers' official pages, numbered at the bottom of the page.

Try it free

7-day trial, then €3.95 a month or €39.95 a year.

In short

Choose CLZ if you also catalog comics, movies or video games, or if automatic values for your books matter most. Choose What I Already Own if you collect records and books and want both, on your phone and your computer, for €39.95 a year: the same setup at CLZ comes to €99.80 a year.

Side by side

What I Already Own and CLZ, criterion by criterion
Criterion	What I Already Own	CLZ
Price	What I Already Own€3.95 a month or €39.95 a year, tax included. One subscription for records and books, on your phone and your computer.	CLZPer app and per platform. Mobile: €1.95 a month or €19.95 a year. Web: €3.95 a month or €39.95 a year. Mobile and web: €49.90 a year. CLZ Books and CLZ Music on both: €99.80 a year.¹²³⁴
Free trial	What I Already Own7 days. A card is required up front; nothing is charged if you cancel before the trial ends.	CLZ7 days. No card needed on the web; on phones, the trial runs through the App Store or Google Play and rolls into a subscription. 90-day money-back guarantee.⁵⁶²
Free plan	What I Already OwnNo. Without a subscription, your collection stays viewable and exportable.	CLZNo. Each app requires an active subscription.⁷
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.	CLZiOS and Android apps. CLZ Web in the browser, with a separate subscription.⁸⁵
Barcode scanning	What I Already OwnWith the camera, inside the app, on iPhone and Android alike. No barcode? Search by title or by the matrix number etched in the run-out groove.	CLZWith the camera, in the mobile apps; CLZ Books can also read the printed ISBN. On the web, scanning goes through the free CLZ Scanner app.⁹⁸
What you can catalog	What I Already OwnRecords (vinyl, CDs, cassettes) and books, in a single collection.	CLZBooks, music, US comics, movies and video games, in five separate apps.¹⁰⁷
Market value	What I Already OwnNo market value shown at this time. You can record the price paid and the selling price.	CLZCLZ Books: automatic value since April 2025, the average of used prices found for an ISBN, regardless of condition. CLZ Music: a value field you fill in yourself.¹¹¹²
Offline	What I Already OwnThe app knows without a signal whether you already own a record or a book; scans made offline are processed once you're back online.	CLZThe mobile apps work on their own; CLZ Cloud is used for backup and sync.⁹
Export	What I Already OwnCSV file, plus an inventory you can print or save as a PDF.	CLZCSV or text from the mobile apps; text and PDF printing on the web.¹³¹⁴
Languages	What I Already OwnEnglish, French, German, Italian, Spanish and Japanese.	CLZMobile apps in English. Web version translated by volunteers, including into French, German and Spanish.⁵¹⁵¹⁶
Where the data comes from	What I Already OwnOpen databases: MusicBrainz, the data dumps published by Discogs, Open Library, the French National Library (BnF), Wikidata. Sources and licenses are published.	CLZCLZ Core, CLZ's own database, updated weekly; for music, the Discogs database as well.¹⁷¹⁸

What CLZ does better

Five categories. If you also collect comics, movies or video games, CLZ covers them; What I Already Own sticks to records and books.¹⁰⁷
Book values. CLZ Books automatically estimates what your books are worth and shows the total; What I Already Own does not show a market value today.¹¹
Track record. CLZ, known as Collectorz.com until October 2024, has been making collection software since 1996, and its apps are on the App Store and Google Play.¹⁹⁵
A no-card trial on the web, and a 90-day money-back guarantee.⁶²

How What I Already Own is different

One subscription. Records and books, phone and computer, for €39.95 a year: the price of CLZ Web for a single category.
The same app everywhere. It installs from the browser on iPhone and Android, and opens on a computer without downloading anything.
What you're missing. For every series, discography or bibliography you've started, the app counts what you have and lists the rest; your wishlist can be shared with friends and family through a link.
Built for the flea market. With no signal, the scan still tells you whether the copy is already on your shelf.
Six languages, including Japanese, for both the app and the catalog.

Try it free

7-day trial, then €3.95 a month or €39.95 a year.

Frequently asked questions

Is What I Already Own an alternative to CLZ?: For records and books, yes: barcode scanning, the exact edition, your collection on your phone and your computer, export. For comics, movies or video games, no: What I Already Own does not catalog them.
How much does CLZ cost for books and records?: CLZ sells CLZ Books and CLZ Music separately, each with a mobile subscription (€19.95 a year) and a web subscription (€39.95 a year), or both for €49.90 a year. Books and records on your phone and your computer: €99.80 a year, based on prices published on September 28, 2026. What I Already Own: €39.95 a year for everything.
Can I bring over my CLZ collection?: Yes, by file: export your collection as CSV from CLZ Web or CLZ Cloud, with the Barcode (records) or ISBN (books) field, then drop it into What I Already Own (Settings, Import a collection). Every item found joins your collection, with its condition, price and purchase date when the export includes them.
Does CLZ tell me what my collection is worth?: For books, yes: CLZ Books estimates each book's value from the used prices found for its ISBN, regardless of condition. For records, CLZ Music leaves the field for you to fill in. What I Already Own does not show a market value today.
Do I need a credit card to try it?: With What I Already Own, yes: a card is required at the start of the 7-day trial, and nothing is charged if you cancel before it ends. With CLZ, the web trial needs no card; on phones, it runs through your App Store or Google Play account.

The catalog, no account needed

The lists What I Already Own keeps up to date for you: discographies, bibliographies and reading orders.

Sources

Pages checked on September 28, 2026. Prices and plans change: confirm them with the publisher before you subscribe.

1CLZ Books, shophttps://shop.clz.com/books
2CLZ Music, shophttps://shop.clz.com/music
3CLZ Bookshttps://clz.com/books
4CLZ Books Web, pricinghttps://app.clz.com/books/pricing
5CLZ Books, App Storehttps://apps.apple.com/us/app/clz-books-book-inventory/id318799163
6CLZ Music Webhttps://clz.com/music/web
7CLZ, bundles and subscription policyhttps://shop.clz.com/bundles
8CLZ Books Webhttps://clz.com/books/web
9CLZ Books Mobilehttps://clz.com/books/mobile
10CLZhttps://clz.com/
11CLZ Books, Book values FAQhttps://clz.com/books/mobile/manual/ios/2.0/en/topic/book-values-faq
12CLZ Music, Field referencehttps://clz.com/music/mobile/manual/ios/2.0/en/topic/field-reference
13CLZ Music, Export to Text/CSVhttps://clz.com/music/mobile/manual/ios/2.0/en/topic/export-to-text-csv
14CLZ Music Web, Print to PDFhttps://app.clz.com/music/manual/1/en/topic/print-to-pdf
15CLZ Club, Set languagehttps://club.clz.com/t/set-language/23189
16CLZ blog, translationhttps://clz.com/blog/tag/translation
17CLZ Music, App Storehttps://apps.apple.com/us/app/id317997093
18CLZ Music Mobilehttps://clz.com/music/mobile
19CLZ blog, Collectorz.com is now CLZhttps://clz.com/blog/news/2024/10/17/collectorz-com-is-now-clz-with-a-new-logo-and-a-new-website-at-clz-com

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].