GFR (glomerular filtration rate — a measure of how well your kidneys filter) and creatinine are blood tests your care team uses to check kidney health. A GFR of 60 or more is in the normal range. A GFR below 60 may mean kidney disease. A GFR of 15 or less is called kidney failure, when dialysis or a transplant is often needed. Creatinine is a waste product from the normal breakdown of your muscles. Healthy kidneys remove creatinine from your blood. Providers use creatinine levels to estimate your GFR. As kidneys become more damaged, creatinine builds up and GFR falls. Kidney disease tends to get worse over time, so these numbers can shift between visits. You cannot raise your GFR, but working with your care team may help keep it from going lower. At each visit your provider will compare your current numbers to past results. Ask what your numbers mean and how they compare to last time.