Is ctlgs free to use?

There is nothing to pay. No subscription, no paid tier, no ads, and no fee when you sell something. That is the short answer; the rest of this page is the detail.

Is ctlgs free to use?

Yes. Browsing needs no account at all. Adding an entry, correcting someone else's, recording what you own, building a shelf and listing a copy for sale are all free as well. There is no price list, because there is nothing to buy.

Is there a paid tier?

No. Everyone signed in gets the same site: no upload limit you can buy your way out of, no pro collection, no field held back behind a payment. There is no payment code in ctlgs — no card form, no checkout, no billing of any kind.

Does selling a copy cost anything?

No, and it cannot, because no money passes through the site. A listing puts a copy you already own in a For sale section on the entry page, with its condition and an optional price. Contact seller opens a private message on the forum, and you and the buyer settle the rest between yourselves — price, payment, postage. ctlgs is not a marketplace and takes no cut. Selling from your collection is the longer version.

Are there ads or trackers?

No ads and no ad network, and nothing on a ctlgs page is loaded from an advertiser or an analytics company. What you read and what you own is not sold to anyone. The site keeps its own log of the pages signed-in members request, so the people running it can see which parts get used; those rows are deleted after 90 days and go nowhere else.

What do I need in order to sign in?

A forum account at forum.ctlgs.org. One account covers the forum and the catalogs, so registering once gets you both, and it costs nothing. If you had an account on one of the old sites, your contributions and your old collection can be attached to it — bring your old account over explains how to ask.

Can I get my collection data back out?

Yes, as a CSV. Every collection has an export at /collection/{username}/export.csv, one row per copy: the entry it points at, its condition and your note. Your own download also carries the location, what you paid, the currency and when you acquired it. Those four are owner-only, so an anonymous download of a public collection leaves them out.

Worth saying plainly, because it is the thing people ask before they start: if you spend an evening typing in four hundred books, the typing is yours, and a spreadsheet of it is one link away whenever you want it. Collections and wantlists covers what goes into a copy in the first place.