From the back cover:
Contains 95 durable, laminated cards that expand the options available for spellcasters of all types. Features brand new spells that can be found in Xanathar's Guide to Everything.
Incorporates Spellbook Cards: Elemental (43 spells) and 52 additional spells introduced in Xanathar's Guide to Everything.
2017 Printing has 96 total cards - Spellbook Cards: Elemental (43) and 52 spells (Xanathar's Guide) + 1 Xanathar's Spells "Reference Card"