Every Grookey card we price, most valuable first. Prices are what copies actually sold for, updated daily.
What a Grookey card is worth
The most valuable Grookey on this list is Grookey from Mega Evolution Promo at $3.27£2.46€2.88, and the 13 priced copies across 11 sets are worth $17£13€15 together. Most of that sits in a handful of printings: the older the set and the scarcer the print run, the wider the gap to the rest.
Grookey is printed in Japanese as well: 10 cards across 6 sets, the most valuable of them Grookey (Master Ball Pattern) from Terastal Fest ex at $4.43£3.33€3.90. Switch the list above to Japanese to read those, or to Both to rank the two catalogues against each other.
The highest PSA 10 on record for Grookey sold for $185£139.24€162.92. reverse holo printings are priced separately from the standard card, because they do not trade at the same money.
If you are trying to identify which Grookey you have, the set name is printed on the card and the collector number sits in the bottom corner. Open the card here and the page carries every printing of it, the graded prices, and whether grading the copy is worth the fee. Sets to start with: Mega Evolution Promo, Shining Fates: Shiny Vault, First Partner Pack.