Kansas transportation officials said about 300 of the 61,000 applications for vanity plates are rejected each year.
The Kansas Department of Revenue's Division of Vehicles said its list of banned plates includes nearly 1,200 entries, including curse words, racial slurs, sexual references and slang terms, The Wichita Eagle reported Monday.
Donna Shelite, director of vehicles, said applicants will "go to all kinds of lengths" to attempt to circumvent the list, including using "ph" in the place of the letter "f" or using numbers in place of similarly shaped letters, such as a "5" to mean "s."
Shelite said officials sometimes need to search the Internet or consult with young people to decode the applications.
"There are some I don't understand," Shelite said.
Vanity plates, which can have as many as seven characters, cost $45 in addition to registration.