Built on official CMS grouping logic · V43.1 · For validation & education · Implementation notes API for developers →

This grouper implements the official CMS MS-DRG specifications using certified grouping algorithms. Results match CMS methodology for educational and validation purposes. For billing and compliance, verify results against your organization’s certified grouper software. Independent implementation not affiliated with CMS.

NEW

V44.0 Available Early for Testing (FY 2027)

V44.0 takes effect for discharges on or after October 1, 2026. We've loaded it early so you can test against the new logic ahead of go-live — 14 new MS-DRGs, 18 retired, updated relative weights, and 190 new diagnosis codes. For discharges before October 1, keep using V43.1. If you encounter any issues or unexpected results, please use the Feedback button to let us know.

Inpatient · CMS MS-DRG

MS-DRG Grouper

Calculate Medicare DRG assignments from ICD-10 codes with validation errors and HAC logic

Patient Info ?Fill in age, sex, discharge status, and grouper version. Age and sex rarely affect DRG — defaults work for most cases. Age and sex rarely affect DRG assignment — defaults are fine for most cases.

Diagnoses

0 entered
Admit diagnosis ?Optional since v43.0. The diagnosis recorded at the time of admission, which may differ from the principal diagnosis. Optional — recorded at admission, may differ from principal
Code
Description
A
Principal diagnosis * ?Required. The condition established after study to be chiefly responsible for the admission. Type a code or description to search. The condition chiefly responsible for admission
Code
Description
POA
P
Secondary diagnoses ?Add comorbidities and complications. These affect CC/MCC severity and can change the DRG. Set POA indicators to affect HAC logic. Comorbidities and complications that set the severity tier
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Code
Description
POA
0 of 0 rows filled

Procedures ?Enter ICD-10-PCS procedure codes. Procedures determine if the DRG is medical or surgical, and can affect the specific DRG within those groupings.

0 entered
#
Code
Description
Surgical procedures route to an O.R. DRG
Not yet grouped
No result yet
Enter the encounter, then Calculate DRG.

About This Tool

Hey there! I'm a solo developer building tools for healthcare operations. I built this to make DRG grouping easier — whether you're coding a single chart or validating your EMR's grouper output. Enter your codes and get results. That's it.