Contact
Dewey Lookup is a one-person project, so a real person reads what comes in. Good things to write about:
- A number looks wrong. Helpful to know, though remember the numbers come from other libraries’ catalog records (Open Library, the Library of Congress and others) — if their record is off, the fix ultimately lives there. Still, tell me and I’ll take a look.
- A feature you wish existed. A reading-recommendation helper, a booktalk writer, a newsletter drafter, a program planner — these are on the someday list, and hearing what solo librarians actually need moves things up it.
- You found it useful. Always nice to hear, and it keeps the lights on.
Email: [email protected]
Bulk and programmatic access
Everyone can use the lookup and the batch list freely. No account, no permission needed.
Need numbers for a whole collection at once? Email [email protected] with a CSV of ISBNs (one per line) and a line about your library. I’ll run it for you overnight, at a pace that’s polite to the libraries whose catalogs make this tool possible, and send back a CSV with a Dewey number and its source for each book I can find. A few thousand books takes two or three nights. This is free for non-commercial library use.
Some results only appear on this website. A few sources share their data with Dewey Lookup on the understanding that it’s shown here, to the librarian looking it up, and not passed on to other systems. Those rows come back marked “excluded”. You can still look those books up here, one at a time.
Looking for an ongoing API for your catalog system? Tell me about it. There isn’t one yet, and it’ll be built once enough libraries need it. Your request counts.
Dewey Lookup never provides catalog records, only suggested numbers with their sources. As always, the number is a defensible candidate. The judgment is yours.