https://scryfall.com/docs/api/cards - link to Scryfall’s data dictionary

Draft Boosters

These are the 15-card draft boosters you know and love. They cost around $4 and have the following cards:

10 common3 uncommon1 rare/mythic

There’s also a 33% chance that a traditional foil of any rarity takes the place of a common card.

Set Boosters

Originating in Zendikar Rising, set boosters have become a regular part of Magic’s pack repertoire. These are slightly different from draft boosters in a few ways. They have 12 or 13 cards instead of 15, and their card distribution is pretty complicated:

1 art card (5% chance of a “signature” variant)

1 land (15% chance of a foil land)

6 “connected” (commons and uncommons with a common type/theme):

35% chance of 5 commons, 1 uncommons40% chance of 4 commons, 2 uncommon12.5% chance of 3 commons, 3 uncommons7% chance of 2 commons, 4 uncommons3.5% chance of 1 common, 5 uncommons2% chance of 6 uncommons

1 “showcase” variant

2 wildcards of any card/rarity:

49% chance of 2 commons24.5% chance of 1 common, 1 uncommon17.5% chance of 1 common, 1 rare/mythic3.1% chance of 2 uncommon4.3% chance of 1 uncommon, 1 rare/mythic2.6% chance of 2 rare/mythics

The rare and mythics may be “showcase” variants

1 rare/mythic (13% chance on mythic, 1/7.4)

1 foil of any card/rarity

1 token/ad card with a chance of being a card from “the list”