What the notes mean
Excludes1 means "not coded here." The two codes should not be reported together, for example a congenital and an acquired form of the same condition. The ICD-10-CM guidelines allow one exception: when the two conditions are unrelated to each other, both codes may be reported.
Excludes2 means "not included here." The excluded condition isn't part of the code, but the patient can have both at the same time. When both are present, both codes may be reported.
How the check works
The tool looks at the Excludes1 and Excludes2 notes on each code and on every level above it (subcategory, category, block and chapter), in both directions, using the official CMS ICD-10-CM tabular list.
This tool checks ICD-10-CM excludes notes only. It doesn't check NCCI edits, medical necessity, or payer-specific rules, and it isn't coding advice. Always confirm against the code book and the documentation.