Setting quantity for duplicate copies

If you own multiple copies of the same volume — a reading copy and a display copy, or one in two different printings sharing an ISBN — you can track quantity rather than creating duplicate entries.

How to set quantity

On the manga detail page:

1. Find the Quantity field.
2. Tap to open the quantity picker.
3. Use the + and − buttons to adjust, or tap the number to type a value directly.
4. Tap outside or back to save.

Default quantity is 1 for newly added volumes.

How quantity affects your collection

Quantity changes how a volume contributes to certain stats:

• Collection value (PRO) — Calculated as MSRP × quantity × condition_multiplier. So 2 copies are valued at 2× a single copy.
• Total volume count on profile — Each unique volume entry counts as 1 toward “X volumes” on your profile, regardless of quantity. (We track unique titles, not stack height.)
• Achievements — Most volume-count achievements use unique volumes, not quantity. So owning 5 copies of one volume doesn’t unlock the “5 volumes owned” achievement on its own.

Why quantity instead of separate entries?

If you have two copies of Chainsaw Man Vol. 5, creating two separate entries would clutter your Library. Quantity keeps things tidy while still tracking that you have multiple physical copies.

The trade-off: you can’t track different conditions or values per copy. If you have a Mint copy and a Fair copy of the same volume, you may want to use the custom value override (PRO) and a notes field, or accept the average condition.

When to use multiple entries instead

For genuinely different physical objects sharing an ISBN — for example:

• Standard edition and signed edition (same ISBN, different value).
• Reading copy and shrink-wrapped collector copy (very different conditions).

…you may prefer two separate entries. To create a second entry, scan the ISBN and tap Add Anyway when the duplicate detection prompts you. See Scanning duplicate ISBNs.

Quick Scan and quantity

When Quick Scan detects a re-scanned volume (same ISBN as one you already own), it skips the add — it does not automatically increment quantity. To bump quantity, you’ll need to do it manually after.

Resetting quantity

If you decrement quantity to 0, the volume isn’t deleted — it stays at quantity 1 (we don’t allow 0). To remove a volume entirely, use Delete from Collection at the bottom of the detail page.

Quantity in exports

When you export your collection, each volume has a quantity field. Importing the same data (or comparing across exports) preserves the quantity correctly.