We do not collect any data that isn’t strictly required in order to operate the integration. For example, if eBay requires only to log in in order to fetch an authorization for posting a listing, the only data related to the user we retain is the name of the store and the token. We will never ask for your private nor banking data outside of the billing addresses. However, for VAT liable business users we will need some data related to your business in order to create invoices. We keep images provided by users and the CSV files for 5 days and delete them afterwards.

Catalogarius is a cooperative project made by experts in the fields of antique books, maps, stamps, postcards and other antiques. Some are former auction house experts, while others are veterans of e-commerce with decades of experience selling on platforms. The idea was formed in mid 2025 with the goal of creating a platform that would speed up listing times.

Yes. Here are some examples:
Stamps take 5-7 minutes to list from start to finish. While it takes 30 seconds to make and process a photo, the rest of the time is spent on identification, description, catalog number ID etc. Our system can handle up to 50 items at once and the average processing time for stamps is 20-32 seconds. For a rounded-up processing time of 30 seconds, Catalogarius can list 6000 stamps/hour.
Books take 12-25 minutes to list, depending on rarity and available information. The samples we took were for mid and low rarity books. The average time for taking and processing photos is 2 minutes; the rest is for identification and listing. Catalogarius can list up to 2 000 books/hour considering that the processing takes 40 seconds and that our servers can handle up to 50 requests at the same time.

Please check our updates page regularly.

We can adjust the system to support other platforms as well, but developing integrations can take time. In case you would like to commission us for listing on a specific platform, please contact us.

Each model we create is specific for a certain type of item on a certain platform. The same model doesn’t work for books on eBay and stamps on Delcampe. Same goes for models specific for platforms as each platform accepts files of different CSV formats and has different limitations in terms of keywords, category sorting and specifics.

As of Q2 2026 we can support only English descriptions. Creating a new model in other languages is possible as a custom project. Contact us for more information.

While we do not currently offer a subscription-based service, the minimum fee stated on the pricing page is not refundable.

Some items are easier to identify, process and have a different required minimal number of photos. Other items such as books require processing of multiple images and looking through different archives, bibliographies and catalogs. This process consumes significantly more resources and is billed accordingly.

No, we do not provide any sort of mediation service.

We can integrate our system to your pipeline so that the staff of the auction house gets notified in case an item is over a certain threshold for evaluation. The threshold is adjustable, and our system can notify the staff if an item is not identifiable.

No, creating estimates and giving certificates of authenticity is beyond the scope of Catalogarius.

Not necessarily. The API keys automatize the process of listing and save you time. However, if you don’t want to share your keys for privacy or security reasons, you can always choose to receive a .CSV/.TXT file that you can upload yourself to the platform of your choosing. Keep in mind that the files will be formatted for the specific platform so you can’t use the same file for listing items on multiple platforms.