Current formulae for estimating glomerular filtration rate(GFR) are derived from large cohorts of stable patients and calculated with single measurements of a circulating biomarker. In acutely unwell patients with rapidly changing renal function, estimating GFR is challenging and often inaccurate.
Kinetic GFR (kGFR) is an estimate of immediate biomarker clearance derived from two discreet measurements which may better represent acute function.

This Calculator can easily calculate a Kinetic GFR for you, and help give you a better understanding of your patients renal function when they are sick and have rapidly changing creatinine

This app accompanies the paper:
The clinical utility of kinetic glomerular filtration rate
Clin Kidney J. 2017 Apr; 10(2): 202–208. doi: 10.1093/ckj/sfw108

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381236/