Prepare source data, inspect a code list and find the right official files. Free access, clear limits and U.S. diagnosis-code context.
Convert a complete CDC/NCHS code-order or code-description file into a spreadsheet. Preserve the original descriptions, preview the results and export on your device.
For researchers and educators: download the free offline research starter kit, including a worked example, Python checks, an R import script and a classroom exercise.
Check up to 100 codes against the selected reference edition. Review catalog presence and code completeness before opening the full entries.
Open the code checker →Explore the FY2027 file library, Index, Tabular List and guidelines. Keep the source release visible throughout a lookup.
Explore the source library →These tools support source preparation and reference checks. They do not diagnose conditions, choose a patient's code or establish claim coverage. Official classification titles and instructions remain in English.
