MedDroidAn eGFR calculator estimates how well your kidneys are filtering waste from your blood. It uses your creatinine blood test result along with your age and sex to give you a number.
What Is eGFR?
eGFR stands for estimated Glomerular Filtration Rate. It is a number that reflects how much blood your kidneys filter each minute. Doctors use it to check kidney health over time, not just on a single day. (Grenier N et al., Semin Nucl Med 2008)
What the eGFR Calculator Does
This tool takes a few details from your lab report and turns them into an eGFR score. It uses a standard formula built into most lab reports already, so this calculator mainly helps you understand or double-check that number.
It does not look at your symptoms, other test results, or medical history. It only works with the numbers you enter.
How to Use the Calculator
You will usually need:
- Your serum creatinine level, from a recent blood test
- Your age
- Your sex
Some versions also ask for race, though many labs in India no longer use this factor. (Choudhary GS et al., Elife 2022)
Enter these details exactly as they appear on your lab report. A typo in creatinine value can change the result a lot.
Understanding Your eGFR Number
eGFR results are usually grouped into ranges that reflect different stages of kidney function. (Nuffield Department of Population Health et al., Lancet 2022) A single result is a snapshot. Kidney function can change due to hydration, illness, medicines, or lab differences, so one low or high number does not confirm a diagnosis.
Your doctor looks at your eGFR alongside other tests, such as urine albumin, and your overall health, before drawing any conclusion.
What Can Affect Your Result
Several things can shift your creatinine level and therefore your eGFR, including:
- Dehydration or recent heavy exercise
- High muscle mass or low muscle mass
- Certain medicines
- Recent illness or infection
- Diet, including high protein intake before the test (Semnani-Azad Z et al., BMJ 2025)
This is why doctors often repeat a creatinine test before deciding anything based on one result.
Limitations of This Tool
This calculator gives an estimate, not a diagnosis. It cannot tell you why your eGFR is high or low. It cannot replace a conversation with your doctor, especially if you have diabetes, high blood pressure, or a known kidney condition, since these change how results should be read.
If your calculator result looks different from the eGFR written on your official lab report, trust the lab report. Labs may use slightly different formulas or rounding.
When to See a Doctor
See a doctor if:
- Your eGFR is below the normal range mentioned on your lab report
- Your eGFR has dropped compared to an earlier test
- You have swelling in your legs or face, unusual tiredness, or changes in how much you urinate
- You have diabetes, high blood pressure, or a family history of kidney disease and have not had a kidney check recently
Bring your lab report to the appointment. A doctor can explain what your eGFR means for you personally and whether you need further tests. Do not change any medicine or start new supplements based on this calculator alone.