ICD-10 Coding Reference

The ICD-10 reference that actually explains the code

Search by code, keyword, or acronym. Get plain-language explanations, risk adjustment mapping across all CMS models (HCC v24 & v28, RxHCC, and ESRD), current CMS guidelines, and the 5 codes most commonly billed alongside it.

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Current CMS & AHA guidelines
Updated every October 1
Risk adjustment — HCC, RxHCC & ESRD
Built for CPCs, billers & CDI specialists

Why coders choose Lynceus

Designed for the work, not just the lookup

Every feature was built around a frustration real coders have with every other tool on the market.

Plain-language explanations

Codes that speak plain English, not bureaucratic Latin

Every code comes with a clear, clinically accurate explanation written for working coders — not researchers. Understand at a glance whether J18.9 means lobar pneumonia, bronchopneumonia, or unspecified without digging through source documents.

  • Plain-English definition alongside the official description
  • Excludes 1 & Excludes 2 notes clearly labeled and explained
  • Clinical context drawn from current CMS and AHA guidelines
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J18.9 Pneumonia, unspecified organism

A lung infection when the specific germ (bacteria, virus, or fungus) causing it is not documented. Use when chart notes say "pneumonia" without specifying a pathogen.

Commonly coded with

Z87.01 J96.00 R05.9 Z23 J18.1
v24: HCC 114 v28: HCC 127 RxHCC: N/A ESRD: N/A
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Top 5 coded alongside E11.9

I10 — Hypertension 84%
E78.5 — Hyperlipidemia 61%
Z79.4 — Long-term insulin 58%
E11.65 — With hyperglycemia 47%
Z68.35 — BMI 35-35.9 41%
Co-coding context

The 5 codes most often billed alongside yours

No other reference surfaces billing co-occurrence data at the point of lookup. See which codes real coders pair with this one — catch missed diagnoses, avoid upcoding risk, and code more completely from the first pass.

  • Real co-occurrence data, not guesswork
  • Reduce denials from incomplete code sets
  • Faster, more complete coding on the first pass
HCC Risk Adjustment E11.9 — Type 2 diabetes, unspecified
CMS-HCC v24

HCC 19 — Diabetes without complication

Risk-Adjusts

MA plan payment rate · blended 33% in 2026

CMS-HCC v28

HCC 37 — Diabetes without complication

Risk-Adjusts

MA plan payment rate · blended 67% in 2026

RxHCC (Part D)

RxHCC 17 — Diabetes

Risk-Adjusts

Part D prescription drug plan risk adjustment

ESRD Model

No mapping

N/A

Not applicable for this diagnosis

Risk adjustment mapping

Every risk model, one lookup — HCC, RxHCC, and ESRD

Lynceus covers all four CMS risk adjustment models at the point of lookup: CMS-HCC v24, CMS-HCC v28, RxHCC (Part D), and the ESRD model. See the category, HCC number, and whether the code risk-adjusts — for every model relevant to your patient population. No spreadsheets, no cross-referencing.

  • CMS-HCC v24 & v28 — MA plan risk adjustment
  • RxHCC — Part D prescription drug plan adjustment
  • ESRD model — dialysis & transplant patient populations
Acronym search

Search "CHF" and get what you actually mean

Clinical acronyms are ambiguous by nature. Type "CHF" and Lynceus surfaces every possible match — then clicking one takes you directly to the full code with explanation, excludes, and co-coding context. No hunting through a flat results list.

  • Possibility list shows every interpretation
  • One click to the full code detail page
  • Also searches by partial alphanumeric code (e.g. "J18" returns all J18.x)
CHF

"CHF" may refer to — select to view full code

Every other ICD-10 tool assumes you already know what the code means. Lynceus is the first one that explains it.

The reference built for working coders, not database administrators

Plain

English definitions alongside every official code description

Current

CMS and AHA guidelines updated every October 1 — no lag

Complete

Co-coding context so you never miss a code that should be there

The scope of ICD-10

Every code. Every update. Every explanation.

70k+
ICD-10-CM diagnosis codes covered
Oct 1
Annual update cadence — always current
5
Co-coding suggestions per code
<1s
Search results — any code, keyword, or acronym

Sourced from CMS official tabular lists and updated to reflect every AHA Coding Clinic advisory. No lag. No guesswork.

See pricing

The difference

Why coders leave the old tools behind

The legacy ICD-10 references were built for database exports, not clinical workflows. Lynceus was built for the person who looks up dozens of codes a day.

What you need Old tools Lynceus
Plain-language explanation of the code Raw description only
Top 5 commonly co-coded diagnoses Not available
Acronym search with disambiguation Keyword only, no disambiguation
Partial alphanumeric code search Exact match only
Excludes 1 & Excludes 2 clearly labeled Buried in raw tables
Risk adjustment — HCC v24/v28, RxHCC & ESRD Not available
Updated every October 1 — zero lag Variable — often weeks behind

Pricing

Priced for individuals and small practices

No enterprise contracts. No per-seat surprises. A straightforward rate that makes sense for CPCs, billers, and CDI specialists working independently or in small teams.

Individual

For CPCs and billers working independently

$12 /month
  • Unlimited code searches
  • Plain-language explanations
  • Top 5 co-coding suggestions
  • Acronym disambiguation
  • Partial code search (e.g. "J18" returns all J18.x)
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14-day free trial. No credit card required.

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Practice

For billing teams and specialty clinics

$39 /month
  • Everything in Individual
  • Up to 5 team seats
  • Search history & recently viewed codes
  • Priority access to new features
  • Email support with guaranteed reply
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Need more than 5 seats or custom EMR integration? Contact us for enterprise pricing.

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Stop looking up codes. Start understanding them.

Join medical coders and billers who trust Lynceus to give them the context, clarity, and co-coding guidance they need — on every single lookup.

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HIPAA-conscious design
Updated every October 1
Built for CPCs & billers