Glomerular Filtration Rate Calculator

Serum Creatinine:
Serum Cystatin C: mg/L
Age: Years
Standardized Assays:
Remove body surface adjustment:
CKD-EPI creatinine equation (2009) mL/min/1.73m2
CKD-EPI creatinine-cystatin equation (2012) mL/min/1.73m2
CKD-EPI cystatin C equation (2012) mL/min/1.73m2
MDRD study equation mL/min/1.73m2


Glomerular Filtration Rate (GFR) Calculator

Our GFR Calculator is a critical tool designed to estimate your kidneys' filtering capacity. By inputting values such as Serum Creatinine, Serum Cystatin C, age, gender, race, and body measurements, you can assess kidney function with precision.


GFR is a key indicator of renal health, reflecting how well your kidneys filter blood. It's measured in mL/min/1.73m², adjusting for body surface area to standardize across different individuals.

Why GFR Matters

Healthy kidneys efficiently remove waste and excess fluids from your body. A decline in GFR can indicate kidney disease, necessitating early intervention to prevent progression.

How to Calculate GFR

We use advanced formulas, including CKD-EPI and MDRD study equations, to calculate GFR. These incorporate factors like creatinine levels, age, and specific patient demographics to provide accurate estimates.

- CKD-EPI Creatinine Equation (2009): Offers improved accuracy over older formulas, especially in higher GFR ranges.
- CKD-EPI Creatinine-Cystatin Equation (2012): Combines creatinine and cystatin C measurements for a more reliable assessment.
- CKD-EPI Cystatin C Equation (2012): Uses cystatin C alone, beneficial when creatinine levels are affected by factors other than kidney function.
- MDRD Study Equation: Widely used, especially for GFR less than 60 mL/min/1.73m², but gradually being replaced by CKD-EPI for its broader applicability.

Using the GFR Calculator

1. Input Measurements: Enter your creatinine, cystatin C levels, age, gender, race, and body measurements.
2. Adjustments: Specify if standardized assays were used and if you need body surface area adjustments.
3. Results: The calculator processes your inputs through multiple equations, presenting estimates of your GFR.

Frequently Asked Questions

1. How is GFR Calculated?
- GFR is estimated using equations that factor in serum creatinine/cystatin C levels, age, gender, race, and sometimes body size.

2. What Should My GFR Be for My Age?
- GFR naturally declines with age. A GFR above 60 mL/min/1.73m² is generally considered normal for most adults.

3. Is GFR Calculated from Creatinine Clearance?
- GFR and creatinine clearance are related but distinct measurements. GFR is a more accurate assessment of kidney function.

4. What is a Normal GFR?
- A GFR over 90 mL/min/1.73m² is considered normal, but values between 60-89 mL/min/1.73m² are often acceptable, depending on age and other factors.

5. What is a Good GFR Result?
- A GFR result within the normal range for your age and demographic group typically indicates healthy kidney function.

6. Is GFR 90 or 60 Normal?
- GFR above 90 is normal. A GFR between 60-89 might be acceptable but warrants monitoring, especially if there are other signs of kidney disease.

7. Can GFR for Kidney Improve?
- In some cases, with appropriate treatment and lifestyle changes, it's possible to stabilize or improve GFR.

8. What is the Most Accurate GFR Calculator?
- The CKD-EPI equations (2009 & 2012) are currently considered among the most accurate for estimating GFR.

9. Will Drinking Water Increase My GFR?
- Hydration can influence creatinine levels, but significant, lasting changes in GFR are generally not achieved merely by altering water intake.

10. Which is Better: GFR or Creatinine Clearance?
- GFR is generally preferred for its accuracy and ease of estimation without requiring 24-hour urine collection.