About Deckhand

What it does

Deckhand answers one question: what can I build with the cards I already own? You tell it what you have — by scanning cards with a webcam or a phone, by pasting a list, or by typing — and it compares that against tens of thousands of real decklists to show which decks you can build today, which ones you are a few cards away from, and what finishing them would cost.

It works for Yu-Gi-Oh! and Magic: The Gathering, with a switch in the header. One account covers both.

What it deliberately does not do

It does not track rarity, set, printing, condition, grading or the market value of your collection over time. A card is a card. That keeps scanning fast — the scanner never stops to ask which printing you are holding — and it keeps the product about building decks rather than about cataloguing cardboard.

How the scanner works

The scanner reads the card’s name with text recognition that runs on your own device — in the browser, or on the phone — and matches it against the card database. No photograph is uploaded, and none is kept. It runs on a laptop with a webcam as well as on a phone, so scanning a collection does not require owning a particular device.

Where the data comes from

• Yu-Gi-Oh! card data, prices and images come from YGOPRODeck, who gave permission for the decklists to be used here.
• Magic: The Gathering card data, prices and images come from Scryfall; decklists from MTGJSON, mtgo.com, Archidekt, EDHREC and the public tournament archives.

Deckhand is unofficial Fan Content permitted under the Fan Content Policy. Not approved/endorsed by Wizards. Portions of the materials used are property of Wizards of the Coast. ©Wizards of the Coast LLC.

Deckhand is an independent tool. It is not produced, endorsed by, or affiliated with Konami, Wizards of the Coast, or any of the sites above, and it sells no cards.

The playtest

A Yu-Gi-Oh! deck can be duelled against a bot, in the browser. The duel runs entirely on your own device and sends nothing about itself to this server; Deckhand writes no card effects. The rules are played by two open-source projects, credited here and on every playtest page with the exact versions a duel runs on:

• Rules engine: the YGOPro core (MIT licence), via koishipro-core.js 1.5.5, with the numbers the engine needs for each card from the YGOPro card database.
• Card behaviour: the YGOPro card scripts @ b83db1cc3f (GPL-2.0), served as separate files and unmodified, except for 10 bug fixes every duel plays and the cards that play their period text in Goat duels (9) and Edison duels (20). Each of those is Deckhand’s own version of the upstream script, GPL-2.0 and derived from it, published at the fixes and overrides.

The engine and the scripts are the work of their authors, who are not affiliated with Deckhand. A playtest is a sandbox, not a ruling — the terms say what that means.

Who makes it

Deckhand is built by one person, for people who keep their cards in shoeboxes and binders and would like to know what is in them. Questions, bug reports and ideas are welcome — see the contact page.