The Certified Guaranty Company (CGC) is a well known collectibles grading service, having been the leader in the comic book grading space for years. While originally founded in New Jersey in 2000, they are currently based in Florida. The trading card branch of the company merged with Certified Sports Guaranty (CSG) earlier in 2023, positioning themselves to compete with the other major players in the card grading industry.
The grading scale is similar to the other non-PSA companies with a 10 point scale and half point grades. They too have multiple levels of a 10, with both a Pristine (Gold) and Gem Mint version.
The CGC slab comes with a QR code for verification, which in my opinion is an improvement over a number you have to punch into a website. You can also search their population report on the website.
CGC is very popular among the Trading Card Game (TCG) community, and they’ve encapsulated double the TCG and non-sports cards than they have sports cards.