Level of Detail in Coding

1. ICD-10-CM codes with 3, 4, 5, 6 or 7 characters ICD-10-CM is composed of codes with 3, 4, 5, 6 or 7 characters. Codes with three characters are included in ICD-10-CM as the heading of a category of codes that may be further subdivided by the use of fourth, fifth, sixth or seventh characters to provide greater specificity.