Kidney Health Checker — Free eGFR & ACR Calculator (2025)

Our Kidney Health Checker helps you understand your kidney status in minutes using eGFR (estimated glomerular filtration rate) and optional uACR/ACR (urine albumin-to-creatinine ratio). It’s designed for speed, clarity, and global usability—supporting both mg/dL ↔ µmol/L and mg/g ↔ mg/mmol conversions. The tool uses the CKD-EPI 2021 creatinine equation (no race) and classifies results using the KDIGO (Kidney Disease: Improving Global Outcomes) framework—today’s most widely adopted approach for CKD evaluation. National Kidney FoundationKDIGO

Important: This is educational information—not medical advice. Only a healthcare professional can diagnose chronic kidney disease (CKD), which requires abnormalities to be present for ≥3 months. Repeat testing is essential if any single result is borderline or abnormal. KDIGO

What the Kidney Health Checker does (and why it matters)

1. Estimates eGFR using CKD-EPI 2021 (creatinine):
   The equation is:
   eGFR=142×min⁡(Scr/K,1)α×max⁡(Scr/K,1)−1.200×0.9938Age×(1.012 if female)\text{eGFR} = 142 \times \min(S_{cr}/K,1)^{\alpha} \times \max(S_{cr}/K,1)^{-1.200} \times 0.9938^{\text{Age}} \times (1.012\ \text{if female})eGFR=142×min(Scr​/K,1)α×max(Scr​/K,1)−1.200×0.9938Age×(1.012 if female)
   where K=0.7K=0.7K=0.7 for females and 0.90.90.9 for males; α=−0.241\alpha=-0.241α=−0.241 (female) or −0.302-0.302−0.302 (male). This formula removes race adjustments and is recommended by major kidney organizations. National Kidney Foundation+1
2. Classifies albuminuria (A-category) if you provide ACR:
   KDIGO albuminuria categories are A1 <30 mg/g, A2 30–300 mg/g, A3 >300 mg/g. We also accept mg/mmol and convert automatically. National Kidney FoundationKDIGO
3. Combines G-category (from eGFR) and A-category (from ACR) to map risk:
   KDIGO’s color-coded grid (often called the “heat map”) relates GFR and albuminuria to risk levels—low, moderately increased, high, or very high—for kidney outcomes. KDIGO
4. Makes results understandable:
   You’ll see clear labels (e.g., G3a, A2) with educational callouts about blood pressure, diabetes, and NSAID use—major, modifiable risk factors for progression.

How the Kidney Health Checker works (step by step)

1. Enter age and sex.
   The eGFR equation includes age and a small sex-specific factor for accuracy. National Kidney Foundation
2. Enter serum creatinine and select units.
   If your lab reports µmol/L, we convert to mg/dL using the standard factor (1 mg/dL = 88.4 µmol/L). scymed.com
3. Optionally enter urine ACR and units.
   If you know your ACR, add it. ACR is the preferred test to assess urinary albumin on a spot sample—and is more reliable than dipsticks for early kidney damage. NIDDK+1
4. See your eGFR, G-category, A-category, and risk indication.
   Our tool presents the G×A combination aligned with KDIGO, plus simple educational guidance to discuss with your clinician. KDIGO

Understanding your results (in plain language)

• eGFR (kidney filtering function):
  Higher is generally better. eGFR is estimated from creatinine, age, and sex using CKD-EPI 2021 to avoid racial adjustments and improve equity. National Kidney Foundation+1
• Albuminuria (uACR/ACR):
  Albumin in urine is often the earliest sign of kidney injury. A uACR >30 mg/g is considered albuminuria and signals risk; repeated checks help confirm and monitor. NIDDK
• KDIGO staging and risk:
  CKD status is described by Cause, GFR category (G1–G5), and Albuminuria category (A1–A3)—the CGA model. Even with the same eGFR, a higher ACR means higher risk; that’s why both tests matter. KDIGO

Remember: One abnormal value does not diagnose CKD; persistence over time (≥3 months) is required. Your provider may repeat labs and consider cystatin-C or combined equations when available for more precision. KDIGONephJC

When should I test kidney health?

You should talk to your clinician about testing if you have risk factors such as diabetes, high blood pressure, heart disease, a family history of kidney disease, are over 50, smoke, or have obesity. Many people with early CKD have no symptoms, so proactive screening matters. MedlinePlus

• eGFR (blood creatinine) and uACR (urine albumin/creatinine) are the two key tests recommended for detection and monitoring. KDIGO
• If a test is abnormal, repeat it—CKD requires persistence over ≥3 months. KDIGO

What raises the risk of CKD progression?

• Hypertension (high blood pressure): Keeping blood pressure in range is essential to slow kidney and heart damage.
• Diabetes: Tight glucose control, screening, and evidence-based medications can reduce albuminuria and risk. American Kidney Fund
• Chronic NSAID use: Long-term use may impact kidney blood flow—discuss safer options with your provider.
• Smoking, obesity, and cardiovascular disease: These amplify kidney and heart risks; lifestyle changes plus medical care can help. MedlinePlus

What to do with your Kidney Health Checker results

• Normal eGFR (G1–G2) and A1: That’s reassuring. If you’re at risk (e.g., diabetes or high BP), continue periodic checks and healthy habits. KDIGO
• Borderline or abnormal: Share your results with your clinician. They may repeat labs, evaluate blood pressure, medications, and consider additional tests (e.g., cystatin-C). KDIGONephJC
• High or very high KDIGO risk: This needs prompt medical review and follow-up planning. Early action can slow progression and reduce complications. KDIGO

Why our Kidney Health Checker stands out

• Medically aligned: Uses current CKD-EPI 2021 and KDIGO guidance for consistent, modern results. National Kidney FoundationKDIGO
• Global-ready: Supports common lab units worldwide with accurate unit conversions. scymed.com
• Privacy-first: All calculations run in your browser—no sign-up or data upload required.
• Fast & accessible: Clean UI, keyboard-friendly, mobile-ready, and lightweight.

Expert tips to protect kidney health (general wellness)

• Manage blood pressure: Follow your clinician’s targets; BP control slows CKD progression and lowers heart risk.
• If you have diabetes: Monitor A1C, consider kidney-protective medications as advised, and check uACR regularly. American Kidney Fund
• Use pain relievers wisely: Discuss persistent NSAID use with your provider.
• Don’t smoke: Quitting benefits kidneys and heart.
• Aim for healthy weight, movement, and sleep: Small, sustained changes help.
• Stay hydrated sensibly: Avoid extremes; follow your clinician’s guidance, especially if you have heart or kidney issues.

(These tips are informational; always follow personalized medical advice.)

Internal resources to keep learning (and doing)

• Check your Diabetes Risk Assessment Tool — diabetes is a top CKD driver.
• Log medicines responsibly with the Prescription Checker and Medicine Dosage Calculator.
• Track your general risk with the Symptom Checker and wellness metrics using BMI and BMR tools.

Trusted external references

• KDIGO 2024 CKD Guideline (full PDF & executive summary): staging, albuminuria, persistence (≥3 months), and evaluation practices. KDIGO+1
• National Kidney Foundation (NKF): CKD-EPI 2021 equation details and albuminuria categories. National Kidney Foundation+1
• NIDDK (U.S. NIH): Why uACR is the preferred urine test and what results mean. NIDDK+1

(We link to high-authority sources to help you read more with your clinician.)

Frequently Asked Questions (FAQ)

The Kidney Health Checker gives you a fast, educational snapshot of kidney function and albuminuria, aligned with modern clinical guidance. Use it to start informed conversations with your clinician, track wellness over time, and pair it with healthy habits and regular check-ups. If anything looks concerning—or if you have symptoms like swelling, foamy urine, fatigue, or rising blood pressure—please seek medical advice promptly. KDIGO