Where the manga data comes from

Manga Vault uses its own curated catalog for all manga information — series, volumes, ISBNs, covers, metadata. We do not query external services (like Google Books or ISBNdb) at runtime. Here’s why and what that means for you.

How our catalog works

The catalog is a database we build and maintain ourselves. It contains:

Every series we’ve added.
Every volume of each series.
ISBNs (13-digit and 10-digit where applicable).
Cover art (sourced from publishers, with rights or fair use).
Author and publisher information.
Release dates and MSRP.
Page counts, descriptions, genres.

When you scan a barcode or enter an ISBN, we look it up in this catalog locally on your device (or in the cloud-synced catalog) — no external API call.

Why our own catalog

External services have limitations:

Inaccurate data — Many manga entries on third-party sources are mislabeled, duplicated, or have wrong covers.
Inconsistent quality — Coverage varies wildly by series and language.
Reliability — Depending on a third-party API for every scan would slow the app and create failure points.
Cost and rate limits — Many APIs charge per query or have strict rate limits.
Privacy — Sending every ISBN you scan to a third party isn’t great for privacy.

By maintaining our own catalog, we control quality, consistency, performance, and privacy.

How we add new entries

Two main paths:

Bulk catalog updates — We periodically import new releases from publisher data sources, manga distributor catalogs (like TOKYOPOP, Viz, Kodansha, etc.), and verified bibliographic sources.
User requests — When users scan a volume that’s not yet in our catalog, they can request it. Our team manually reviews and adds. See Requesting a manga.

How accurate is the catalog

Our catalog is well-maintained for:

Mainstream English-language manga (high accuracy).
Major French, German, Italian, Polish, Spanish, Brazilian Portuguese, and Japanese editions (good accuracy).
Recent releases (kept current within days to weeks).

Accuracy is lower for:

Out-of-print volumes from before our catalog era.
Obscure indie or self-published titles.
International editions in less-covered languages.

If you spot an error, contact support and we’ll correct it.

What if the catalog is wrong about a volume

Common issues:

Wrong cover art — We use the most common edition’s cover. If your specific printing has a different cover (variant, alternate edition), we may show the more common one. Let us know and we’ll add the variant.
Wrong title — Sometimes localized titles or alternate edition names get conflated. Report and we’ll fix.
Wrong page count or release date — Same — report and we’ll verify and update.

The bundled catalog

When you install Manga Vault, an initial catalog snapshot is bundled with the app. This means scanning works immediately, even before any cloud sync, and it’s why initial app size is several megabytes.

The bundled catalog updates with each app version release.

The cloud catalog

After install, the app syncs additional catalog data (new entries since the bundled snapshot) from our cloud servers. This keeps your catalog current without requiring frequent app updates.

Catalog version

You can see your current catalog version in Settings → About → Catalog Version. The version number increments as we publish new catalog updates.

Privacy: scanning doesn’t phone home with your scans

When you scan a barcode, the lookup happens on your device against your local catalog data. We don’t send your scans to a tracking service.

We do log catalog requests (when you submit a request for a missing ISBN), but routine scans of in-catalog ISBNs don’t generate server-side logs of what you’re scanning.

What if a volume is in the catalog but I think it shouldn’t be

If we have an entry that’s clearly wrong (e.g., a non-manga product mistakenly cataloged as manga), contact support with the ISBN and we’ll review.

Catalog gaps

If your collection has volumes we don’t have in our catalog, request them. We prioritize requested volumes and approve quickly.

The more users use Manga Vault and submit requests, the faster catalog coverage grows.