Estimate your glomerular filtration rate using the latest CKD-EPI 2021 formula (no race adjustment). Determine your CKD stage and compare results with the MDRD formula for comprehensive kidney health assessment.
A 30-year-old male with serum creatinine 0.95 mg/dL.
CKD-EPI 2021 eGFR: ~107 mL/min/1.73mยฒ
CKD Stage: Stage 1 (normal kidney function)
MDRD eGFR: ~97 mL/min/1.73mยฒ
This indicates excellent kidney function with no signs of impairment. The CKD-EPI formula typically gives slightly higher values at normal GFR compared to MDRD.
A 55-year-old female with serum creatinine 1.1 mg/dL.
CKD-EPI 2021 eGFR: ~56 mL/min/1.73mยฒ
CKD Stage: Stage 3a (mild to moderate decrease)
This patient has about 47% of normal kidney function and should discuss management with their healthcare provider.
A 68-year-old male with serum creatinine 1.8 mg/dL.
CKD-EPI 2021 eGFR: ~41 mL/min/1.73mยฒ
CKD Stage: Stage 3b (moderate to severe decrease)
At this stage, patients should receive regular nephrology follow-up, monitor for complications, and manage cardiovascular risk factors.
A 72-year-old female with serum creatinine 3.5 mg/dL.
CKD-EPI 2021 eGFR: ~14 mL/min/1.73mยฒ
CKD Stage: Stage 5 (kidney failure)
This indicates severely reduced kidney function requiring nephrology evaluation for renal replacement therapy options including dialysis or transplantation.
The estimated Glomerular Filtration Rate (eGFR) is a key indicator of kidney function. It estimates how well your kidneys are filtering waste products from your blood. eGFR is calculated using serum creatinine levels along with age, gender, and other factors โ no race adjustment is used in the latest guidelines.
| Stage | eGFR (mL/min/1.73mยฒ) | Description |
|---|---|---|
| Stage 1 | โฅ 90 | Normal or high kidney function (kidney damage present) |
| Stage 2 | 60โ89 | Mildly decreased kidney function |
| Stage 3a | 45โ59 | Mild to moderately decreased kidney function |
| Stage 3b | 30โ44 | Moderately to severely decreased kidney function |
| Stage 4 | 15โ29 | Severely decreased kidney function |
| Stage 5 | < 15 | Kidney failure |
eGFR estimates how well your kidneys filter waste. A normal eGFR is typically โฅ 90 mL/min/1.73mยฒ. Values decline naturally with age.
Serum creatinine levels can be affected by muscle mass, diet, hydration, exercise, and medications. Tell your doctor about all medications you take.
The CKD-EPI 2021 formula eliminates race as a factor, addressing historical disparities in kidney function assessment. This is the current NKF/ASN recommended approach.
A single eGFR value is less meaningful than the trend over time. A sustained decline in eGFR over months is more concerning than a single low reading.
Estimated Glomerular Filtration Rate (eGFR) is a blood test result that tells your healthcare provider how well your kidneys are working. The kidneys filter waste products and excess fluid from your blood, which are then excreted as urine. eGFR is calculated from your serum creatinine level, age, and gender using validated equations.
An eGFR of 90 mL/min/1.73mยฒ or higher is considered normal. Values below 60 for three months or more indicate chronic kidney disease (CKD). Early detection of reduced kidney function is critical because CKD often progresses silently โ many people don't experience symptoms until kidney function is severely impaired.
Our Kidney Function Calculator uses the CKD-EPI 2021 formula, which is the current standard recommended by the National Kidney Foundation (NKF) and Kidney Disease: Improving Global Outcomes (KDIGO). This formula eliminates race adjustment, reflecting the latest medical consensus for equitable and accurate kidney function assessment.
Chronic Kidney Disease is classified into six stages based on eGFR. Each stage represents a different level of kidney function and guides clinical management decisions:
The Modification of Diet in Renal Disease (MDRD) formula was the standard for eGFR estimation for many years. While still used in some clinical settings, it has been largely replaced by the CKD-EPI 2021 formula for several important reasons:
The MDRD formula systematically underestimates eGFR in people with normal or near-normal kidney function (eGFR > 60). CKD-EPI provides more accurate estimates across the full range.
The CKD-EPI 2021 formula removes race as a factor, addressing long-standing disparities. The MDRD formula included a race adjustment that could lead to misclassification.
CKD-EPI reduces the number of false-positive CKD diagnoses (especially in older adults and women), leading to more appropriate clinical management.
The NKF, ASN, and KDIGO all recommend CKD-EPI 2021 as the preferred formula for eGFR estimation in clinical practice.
While eGFR is a powerful tool for assessing kidney function, several factors can influence your results. Understanding these can help you and your healthcare provider interpret your values more accurately:
Creatinine is produced from muscle metabolism. People with very high muscle mass (bodybuilders) or very low muscle mass (amputees, elderly, malnourished) may have creatinine levels that don't accurately reflect their true GFR.
Eating a large amount of cooked meat shortly before a blood test can temporarily increase serum creatinine levels, potentially leading to a falsely low eGFR.
Certain medications can affect serum creatinine levels or creatinine secretion. These include some antibiotics (trimethoprim), Hโ blockers (cimetidine), and some chemotherapy drugs.
eGFR naturally declines with age โ a value of 60 in an 80-year-old may be considered normal for their age. However, accelerated decline should always be investigated.
โ ๏ธ Important Medical Disclaimer: This Kidney Function (eGFR) Calculator is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. eGFR values should always be interpreted by a qualified healthcare provider in the context of your complete medical history, physical examination, and other laboratory tests. Do not change your medications or treatment plan based solely on the results from this calculator. If you have concerns about your kidney function, please consult a nephrologist or your primary care provider.