GFR Calculator

GFR calculator helps you calculate glomerular filteration rate, useful to assess renal function in chronic kidney disease.

Glomerular Filteration Rate (GFR)

Glomerular Filtration Rate (GFR) is a measure of the rate at which the kidney filters blood to remove waste products and excess fluid, ultimately producing urine.

The GFR calculator is a powerful tool used to estimate the efficiency of the kidney in filtering the waste products from the blood. The glomeruli, a tiny structure in the kidney responsible for filtering blood, measure the rate at which they filter blood.

The GFR calculator offers a user-friendly and accurate way to estimate the GFR based on the key parameters. GFR is a crucial indicator of kidney function and overall kidney health. The GFR calculator estimates the GFR to help you assess the kidney function and identify potential problems.

Glomerular filtration rate (GFR) can be calculated by measuring any chemical that has a steady level in the blood, and is freely filtered but neither reabsorbed nor secreted by the kidneys. The rate therefore measured is the quantity of the substance in the urine that originated from a calculable volume of blood. The GFR is typically recorded in units of volume per time, e.g., milliliters per minute ml/min. Compare to filtration fraction.

GFR Formula Calculate GFR

There are several different techniques used to calculate or estimate the glomerular filtration rate (GFR or eGFR). The Most recent techniques are CKD EPI and MDRD GFR Formula. The details of these GFR Calculation formulas can be see after the calculator. The following GFR Calculator is based on these new GFR Calculation techniques.

CKD EPI & MDRD GFR Calculator - (With SI Units)

4 variable MDRD CKD EPI Equation (with SI Units) using standardized serum creatinine, age, race, gender

Serum creatinine
mg/dL μmol/L

NOTE: CKD EPI GFR is only valid with creatinine methods are traceable to IDMS
Age years
Race African American All other races*
Gender Male Female
TRACEABLE TO IDMS No Yes

CKD EPI Value: epi


MDRD GFR: epi


(Age, Race, Gender, Plasma creatinine)

Chronic kidney disease (GFR less than 60 or kidney damage for at least three months)
*All ethnic groups other than African American


What is a GFR calculator and how does it work?

The GFR calculator measures the kidneys' efficiency in filtering blood and eliminating waste products. GFR is a crucial indicator of kidney function and overall kidney health.

The GFR calculator estimates the GFR based on various factors, although most accurate measurements of GFR are through complex medical tests.

Healthcare providers use the GFR estimations as part of a broader evaluation of kidney function. For accurate diagnosis and treatment decisions, medical professionals must be consulted to interpret the results regarding your overall health and medical history.

What are the units of the GFR calculator?

The essential factors that the GFR calculator considers are age, race, gender, serum creatinine level, and weight in some calculators.

The units of weight used in the calculator are kilograms or pounds. A kilogram is a unit of weight, approximately equivalent to 2.205lb and 1000 cubic centimeters (cm) of water. According to the imperial system, a pound is a weight measurement unit equal to about 0.45359237 kgs.

Race refers to categorizing and classifying people based on shared physical and genetic characteristics.

The creatinine level is the amount of creatinine in the blood. Creatinine is the waste product generated by muscle metabolism.

How to use the GFR calculator?

The GFR calculator measures the overall index used for kidney function. The functioning of the kidney declines with age. GFR is calculated by measuring any chemical that has a steady flow in the blood without being reabsorbed or secreted by the kidneys.

The units recorded by the GFR are at a rate of milliliters per minute per 1.73 squared meters of body surface area. The formula to calculate the filtration rate is GFR = Urine concentration x Urine Flow/ Plasma concentration

GFR calculator values

Chronic Kidney Disease (CKD) is a condition where the kidneys gradually lose their ability to function normally. The stages of the condition depend on the estimated GFR.

CKD Stages
Stages Description Estimate GFR mL/min/1.73m2
Stage 1 Kidney damage with normal kidney function 90 and higher
Stage 2 Mild loss of kidney function 60-89
Stage 3A Mild to moderate loss of kidney function 45-59
Stage 3B Moderate to severe loss of kidney function 30-44
Stage 4 Severe loss of kidney function 15-29
Stage 5 (end-stage renal disease) Kidney failure or close to kidney failure Less than 15
 

Health implications

CKD can have health implications as it progresses through the different stages. Some of the health implications include:

Management of CKD involves addressing the underlying cause and making lifestyle changes. The changes involve adopting a kidney-friendly diet and monitoring the complications. Early detection and prevention are critical to slow down the progression of CKD and reduce the risk associated with health complications.

The GFR calculator is valuable for estimating kidney function based on critical parameters. By providing an approximation, the calculator provides insights into renal health.

However, it is crucial to recognize that the GFR calculators provide estimations that are not a substitute for professional medical advice. For accurate diagnosis and interpretation of results, consultation with the healthcare professional is essential. Regular monitoring and early prevention are the keys to maintaining a healthy kidney, and the GFR calculator can only play a supporting role in this ongoing process.

References

https://www.britannica.com/science/kilogram
https://www.britannica.com/science/pound-unit-of-weight
https://www.genome.gov/genetics-glossary/Race#:~:text=Definition,nations%2C%20regions%20and%20the%20world.
https://www.mayoclinic.org/tests-procedures/creatinine-test/about/pac-20384646#:~:text=The%20amount%20of%20creatinine%20in,blood%20(micromoles%2FL).
https://www.cdc.gov/kidneydisease/publications-resources/annual-report/ckd-related-health-problems.html#:~:text=Health%20Problems%20Due%20to%20Low%20Kidney%20Function&text=Loss%20of%20appetite%20or%20nausea,bone%20disease%20and%20heart%20disease.