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Why Kidney Function Matters

One in seven American adults has chronic kidney disease (CKD) — and 90% don't know it. Kidney function declines silently, often without symptoms, until significant damage has occurred. The good news: when caught early, CKD progression can often be slowed or stopped through targeted lifestyle changes, blood pressure management, and modern therapies.

This analyzer uses the latest validated equations endorsed by the National Kidney Foundation:

  • CKD-EPI 2021 race-free equation for accurate eGFR estimation
  • KDIGO 2024 CGA classification (Cause, GFR, Albuminuria) for staging
  • Cystatin C integration when available, for greater precision than creatinine alone
Which best describes you?

Choose "At-Risk" if you have diabetes, high blood pressure, family history of kidney disease, or cardiovascular disease.

Enter Your Lab Results

Use values from a recent Comprehensive Metabolic Panel (CMP) and Urine ACR test. Required fields marked with an asterisk (*).

Demographics & Required Labs

Adults 18 and older.

Used for eGFR equation; not gender identity.

Reference range typically 0.6 to 1.2 mg/dL. Found on standard CMP.

Optional — Adds Precision

More precise than creatinine alone (KDIGO 2024 preferred).

Required for complete KDIGO staging.

Health Background

Check all that apply.

Analyzing Your Kidney Function

Please wait — do not press back or refresh

  1. 1 Calculating eGFR using CKD-EPI 2021 equation...
  2. 2 Applying KDIGO 2024 staging classification...
  3. 3 Reviewing supporting lab markers...
  4. 4 Generating personalized clinical interpretation...

This typically takes 30 to 60 seconds — we're applying validated equations and AI clinical analysis.

Don't Have Lab Data Yet?

Order a Comprehensive Metabolic Panel with Cystatin C and Urine ACR through ULTA Lab Tests — no doctor visit required (most states), or book a Physician Interpretation Session to discuss what to test.

Order Labs — ULTA Ask the Doctor — $225

Direct-access lab testing is not available in NY, NJ, RI, or HI.

Sources & Scientific Foundation

Every calculation, threshold, and recommendation in the Kidney Function Analyzer™ is grounded in peer-reviewed research and current clinical guidelines — including the CKD-EPI 2021 race-free equation, KDIGO 2024 staging guidelines, and the validated Kidney Failure Risk Equation (KFRE).

View Full Sources & Citations →

Complete bibliography with peer-reviewed citations and direct links to NEJM, KDIGO, NIDDK, NKF, AJKD, and JAMA.

Show calculation methodology and equation details

eGFR (creatinine-only) uses the 2021 CKD-EPI race-free equation:

eGFR = 142 × min(SCr/κ, 1)^α × max(SCr/κ, 1)^-1.200 × 0.9938^Age × 1.012 [if female]

Where κ = 0.7 (female) or 0.9 (male), and α = -0.241 (female) or -0.302 (male).

eGFR (creatinine + cystatin C) uses the 2021 CKD-EPI combined equation, which is the KDIGO 2024 preferred method when both markers are available:

eGFR = 135 × min(SCr/κ, 1)^α × max(SCr/κ, 1)^-0.544 × min(Scys/0.8, 1)^-0.323 × max(Scys/0.8, 1)^-0.778 × 0.9961^Age × 0.963 [if female]

Where κ = 0.7 (female) or 0.9 (male), and α = -0.219 (female) or -0.144 (male).

KDIGO CGA classification assigns a GFR stage (G1–G5) based on eGFR thresholds (≥90, 60–89, 45–59, 30–44, 15–29, <15 mL/min/1.73m²) and an albuminuria stage (A1–A3) based on UACR thresholds (<30, 30–300, >300 mg/g). Combined risk is shown using the KDIGO heatmap (low/moderate/high/very-high).

AI interpretation uses Anthropic’s Claude Opus 4.6 model. The model receives only the structured numeric results and demographic context shown above; it does not have access to your name, email, or any identifying information. The prompt is constrained to produce educational content with explicit prohibitions against diagnostic, treatment, or curative language.

Disclaimers and Important Information

Educational Use Only

The Kidney Function Analyzer™ provides educational information based on validated clinical equations (CKD-EPI 2021 race-free, KDIGO 2024 staging) and AI-generated interpretation. It is not a diagnostic device and does not replace medical evaluation, advice, diagnosis, or treatment by a licensed healthcare provider.

AI Disclosure

Personalized interpretations are generated using Claude Opus 4.6 (by Anthropic), an artificial intelligence system. AI outputs are based on the data you provide and may contain errors or limitations. Always verify findings with a qualified clinician.

Data Privacy & Security

Your inputs are transmitted via HTTPS to our secure backend, processed in memory to compute results, and discarded immediately after the response is returned. We do not store your lab values, comorbidities, or any health information on our servers. If you choose to email yourself a copy of results, your email address is used solely for that one delivery and is not added to any marketing list. Your data is never used to train AI models.

Equation Limitations

The CKD-EPI 2021 equation may be less accurate in individuals with extremes of muscle mass, pregnancy, certain medications, vegetarian diets, or non-steady-state conditions (acute illness, recent fluid shifts). Cystatin C-based equations are preferred when available. eGFR is an estimate, not a direct measurement of kidney function. Single-point measurements cannot diagnose chronic kidney disease — KDIGO requires abnormalities to persist for at least 3 months.

Accessibility

This tool is built to WCAG 2.2 Level AA standards. Use the accessibility settings bar at the top of the page to enlarge text or enable high contrast mode. If you encounter any accessibility barrier, please contact [email protected].

If You Are in a Medical Emergency

If you are experiencing a medical emergency, call 911 or go to your nearest emergency department.