In 1985 at the age of 11, he won the National Elementary Chess Championship with a perfect 7–0 score (seven wins and no losses), becoming the first African-American to win a national scholastic title and the second African-American to win a national chess championship (Frank Street Jr. was the first, winning the 1965 US Amateur Championship).[2][citation needed]
In 1985, Karanja also received the Laura Aspis Prize, granted annually to the top USCF-rated player under the age of 13.[3] Karanja qualified as the United States representative for the 1986 World Under-14 Chess Championship in San Juan, Puerto Rico.[4]
In 1987, Karanja was selected to the inaugural All-America Chess Team, which recognizes the top 0.1-0.2 percent of chess players age 18 years and younger.[5] Karanja also qualified for the 1987 U.S. Cadet Championship where only the top eight players under age 16 are invited to compete.[6]
In 1989, at the age of 15 years and 7 months, Karanja became a chess master, becoming the second youngest African-American at the time to achieve that feat behind Howard Daniels (15 years, 4 months).[1] He subsequently attended Carleton College.[6]
A sample of Karanja's ability is evidenced in the following game from the 1987 United States Cadet Chess Championship.[10]
Retirement
Karanja retired from tournament play in 1990 with a rating of 2193. Karanja has written one book on chess and while living in Kenya was active in promoting chess.[1]