MS-DRG Calculator

Calculate Medicare inpatient hospital payments under IPPS — real FY2026 rates.

MS-DRG v43.1 · FY2026
Hospital
Length of stay (optional)

Enter admit & discharge dates (LOS is computed), or type LOS directly. It's compared against the DRG's mean stays in the estimate.

Transfer status
Payment scenario

IME & DSH default to the provider's CMS values (from its resident-to-bed and low-income patient ratios). Uncheck to see the payment without a given add-on.

Quality adjustment factors (optional)

Leave unchecked for standard in-network pricing. Check only for out-of-network MA paid claims — it caps the payment at the Medicare-equivalent floor.

Payment breakdown

Search for a DRG above to calculate the payment.
Formula & data coverage
Operating   = [(Labor SA × Wage Index) + Nonlabor SA] × Weight × (1 + IME_op + DSH_op)
Capital     = (Capital Rate × GAF × Weight) × (1 + IME_cap + DSH_cap)
Grand Total = Operating + Capital + Uncompensated Care + Outlier (if cost exceeds threshold)

Coverage: 770 MS-DRG relative weights & length-of-stay values; hospital-specific wage indices by CCN (3,253 IPPS hospitals); national FY2026 standardized amounts; and hospital-specific financials — operating/capital cost-to-charge ratios, IME & DSH adjustment factors, GAF, uncompensated-care per-claim amount, and Hospital-Specific Payment rate (3,103 hospitals). Outlier fixed-loss threshold $40,397 (FY2026).

Not modeled: reconciliation of a hospital's prior-year cost report — IME/DSH/CCR figures here are the FY2026 rule's modeled estimates (the same inputs Medicare uses going into the year); actual settlement can differ slightly. Hospitals without a published wage index — critical access, VA, inpatient psych/rehab (IPF/IRF), long-term care (LTCH) — are paid under other systems this calculator doesn't model; enter a wage index manually for those.

Watch · 1:00 · silent

The whole engine in 60 seconds

Group ICD-10 codes to an MS-DRG, watch one documented MCC move DRG 195 → 193 (+$5,580.76), see the full FY2026 payment build line by line, the 2.5× swing between two hospitals, a live match against the official pricer to the cent, and every estimate exported as a PDF/Excel pricing worksheet. Every figure is real engine output.

© 2026 PayerParity · [email protected]
For developers & platforms

Build on the engine.

Everything this site does is a REST API underneath — group ICD-10 codes to an MS-DRG (any manual version), price the claim with real FY2026 factors, verify it against the official pricer, and export the worksheet. JSON in, JSON out; FHIR R4, vendor and Epic Tapestry claim shapes accepted.

POST /drg/group GET /drg/calculate GET /drg/verify GET /drg/worksheet
Request API access →

Tell us what you're building — keys are issued per organization.
Or email [email protected].

How the MS-DRG Calculator works

This free MS-DRG calculator estimates Medicare inpatient hospital payments under the Inpatient Prospective Payment System (IPPS) using official FY2026 CMS rates. Enter ICD-10 diagnoses and procedures to group a claim to its Medicare Severity Diagnosis-Related Group (MS-DRG), then price it for any IPPS hospital.

The MS-DRG payment formula

Medicare pays a single bundled amount per inpatient stay: Payment = DRG relative weight × hospital base rate. The base rate is split into a labor-related share (adjusted by the hospital's area wage index) and a non-labor share. Additional add-ons are then applied for disproportionate share (DSH), indirect medical education (IME), new-technology, and high-cost outlier cases.

What you can do here

Group ICD-10 claims to an MS-DRG (native, vendor, FHIR R4, or Epic Tapestry formats), price a claim by hospital with a printable worksheet, compare inpatient vs. outpatient (OPPS/APC and ASC) site-of-service payment, and verify results against CMS's own Inpatient PPS pricer.

Frequently asked questions

What is an MS-DRG?

An MS-DRG (Medicare Severity Diagnosis-Related Group) is the classification Medicare uses to pay hospitals a single bundled amount for an inpatient stay, based on the patient's diagnoses, procedures, and severity rather than itemized charges.

How is a Medicare DRG payment calculated?

Payment equals the DRG's relative weight multiplied by the hospital's IPPS base payment rate. The base rate is split into labor and non-labor shares, and the labor share is adjusted by the hospital's wage index. Add-ons for DSH, IME, new technology, and high-cost outliers are then applied.

What is a DRG relative weight?

The DRG relative weight reflects the average resources used to treat a case in that DRG relative to the average Medicare case. A weight of 2.0 pays roughly twice the base rate; 0.5 pays about half.

How does the wage index affect DRG payment?

Only the labor-related share of the IPPS base rate is adjusted by the hospital's area wage index. A wage index above 1.0 raises the labor portion of every DRG payment for that hospital; below 1.0 lowers it.

What is the FY2026 outlier threshold?

For FY2026 the CMS fixed-loss cost outlier threshold is $40,397. Medicare pays an additional outlier amount when a case's estimated cost exceeds the DRG payment plus that threshold, reimbursing 80% of the excess (90% for burn DRGs). This calculator applies the FY2026 threshold and marginal-cost factor automatically.

Is this DRG calculator free?

Yes. The MS-DRG calculator is free to use and runs on official FY2026 CMS IPPS rates and factors.

Independent estimator — not affiliated with or endorsed by CMS. Verify all figures against official CMS files before billing. © 2026 PayerParity.