The app allows you to calculate the glomerular filtration rate based on the concentration of creatinine, age and weight, or the concentration of cystatin C and age, or the concentration of creatinine, cystatin C, age and weight. The calculation is based on five different formulas (KG, MDRD, CKD-EPI (Scr), CKD-EPI (Scys), CKD-EPI (Scr/Sys)), taking into account gender and race. Calculation formulas are selected automatically depending on the amount of data you enter. creatinine can be administered as mg / DL or in mmol / l conversion for each formula will occur automatically. recommendations for the stage of renal failure are derived from the most accurate calculation result.