What is an MS-DRG grouper?

An MS-DRG grouper is a software tool that assigns Medicare Severity-Diagnosis Related Groups (MS-DRGs) based on patient diagnoses, procedures, age, sex, and discharge status. This grouping is essential for Medicare reimbursement and billing purposes.

Is this MS-DRG grouper free to use?

Yes, this online MS-DRG grouper is completely free to use. There's no registration required, no login needed, and no software to install. Just enter your codes and get instant results.

What features does this DRG grouper include?

Our grouper includes real-time ICD-10 code validation, validation error checking, Hospital Acquired Condition (HAC) logic, CC/MCC validation, and Present on Admission (POA) indicator support. It provides instant results and supports all current Medicare MS-DRG versions.

How accurate is this DRG grouper?

This grouper is based on official CMS specifications and is regularly updated with the latest Medicare rules. While highly accurate, it should be validated against your official grouper software for compliance purposes.

Can I process multiple records at once?

While our free online tool processes one record at a time, we offer bulk processing services for large datasets. Contact us for information about processing multiple records for audits, analysis, or EMR validation.

Which MS-DRG versions are supported?

We support multiple MS-DRG versions including V43.0 (FY2026), V42.0 (FY2025), V41.0/V41.1 (FY2024), and V40.0/V40.1 (FY2023). You can select your desired version when grouping.

How do I calculate a DRG online?

Simply enter the patient's age, sex, discharge status, principal diagnosis, and any secondary diagnoses or procedures. Our tool will instantly calculate the appropriate MS-DRG code, weight, and Major Diagnostic Category (MDC) based on official CMS logic.

What are POA (Present on Admission) indicators?

POA indicators show whether a diagnosis was present when the patient was admitted. Values include Y (yes), N (no), U (unknown), W (clinically undetermined), or 1 (exempt). POA status affects HAC (Hospital Acquired Condition) determinations and can impact reimbursement.

Do I need to register or create an account?

No registration, login, or account creation is required. This is a completely free, open-access tool. Simply visit the site and start calculating DRG codes immediately.

How accurate are the DRG calculations?

Our grouper implements CMS's official MS-DRG logic and is regularly updated with the latest specifications. While highly accurate for educational and validation purposes, results should be verified against your certified grouper software for final billing and compliance.

What is the difference between DRG and MDC?

An MDC (Major Diagnostic Category) is a broad body system classification (like Respiratory or Circulatory). A DRG is a more specific payment group within an MDC that considers procedures, complications, and severity. Each DRG belongs to exactly one MDC.

Can I use this for Medicare Advantage or commercial payers?

This tool uses CMS MS-DRG logic, which is primarily designed for traditional Medicare. While many Medicare Advantage and commercial payers use similar logic, they may have proprietary modifications. Check with your specific payer for their grouping requirements.

NEW

FY2026 (V43.0) Now Available

V43.0 grouper is now available with updated logic and code descriptions for FY2026. Learn more about the changes. If you encounter any issues or unexpected results, please use the Feedback button to let us know.

CMS-SPEC COMPLIANT

Built on Official CMS Grouping Logic

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.

MS-DRG Grouper

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

Current version: v43.0 FY2026

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

Age *

Sex *

Discharge Status *

Grouper Version *

Age and sex rarely affect DRG assignment — defaults are fine for most cases.

Clinical Information

Search by code or description

Primary Diagnoses ?Principal diagnosis is required. Add the admit diagnosis if known. Type a code or description to search.

Admit Diagnosis (Optional)

Principal Diagnosis *

Secondary Diagnoses ?Add comorbidities and complications. These affect CC/MCC severity and can change the DRG. Set POA indicators to affect HAC logic.

Procedures ?Enter ICD-10-PCS procedure codes. Procedures determine if the DRG is medical or surgical and can significantly change the assignment.

Results

-

No DRG Assigned

Base DRG

Weight

Type

Major Diagnostic Category

- No MDC Assigned

HAC Impact

No HAC impact

Diagnosis Details

Procedure Details

Errors

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.