Scanning duplicate ISBNs
If you scan a volume you already own, Manga Vault detects the duplicate and stops you from accidentally adding it twice.
What you’ll see
When you scan an ISBN that’s already in your collection, instead of the usual Found card you’ll see a duplicate notice with two options:
- Already Owned — You already have this volume. The notice will tell you when it was added.
- Add Anyway — Adds another copy. The volume’s quantity will increment by 1 (e.g., from 1 to 2).
When would I want to add anyway?
Most often, you have multiple physical copies of the same volume:
- Reading copy + display copy
- Collector’s edition + standard edition with the same ISBN
- One you received as a gift or duplicate purchase
If you tap Add Anyway, the quantity increases on the existing entry rather than creating a separate record. You can also adjust quantity manually from the manga detail screen.
Detecting duplicates while scanning a long list
If you’re cataloging a large collection in Quick Scan mode, duplicates are skipped automatically — the volume isn’t re-added, and you’ll see a brief “Already in your collection” toast instead of the standard “Added” toast.
This is intentional — we’d rather you accidentally re-scan a volume than have to merge duplicate entries afterward.
What about wishlist items?
Scanning an ISBN that’s on your wishlist is treated as a normal scan — you can move it from Wishlist to Owned by adding it. The volume’s status will switch from Wishlist to Owned in your Library.
Different editions, same ISBN
It’s possible (though rare) for two different printings to share an ISBN. If you genuinely have two distinct editions and want to track them separately, you can:
- Add the first one normally.
- For the second, use Add Anyway and then edit the entry from the manga detail page to mark it differently (e.g., add a custom note, change the condition).
I added a duplicate by mistake
Open the manga detail page in your Library, tap Quantity, and decrease it back to the correct number. If the entry is entirely unwanted, tap Delete to remove it from your collection.