Kidney Function Test (KFT / RFT)

The 11 tests in this panel

What each one measures and the range labs usually print for adults. Ranges differ a little between labs, so the range on your own report is the one your result is judged against.

• Urea

  Urea is the main waste product from breaking down protein. Your kidneys clear it from the blood.

  16+

  2.5–7.8 mmol/L

  Men, 18–29

  3–7.5 mmol/L

  Men, 30–49

  3–8 mmol/L

  Men, 50–59

  3.5–8.5 mmol/L

• Blood Urea Nitrogen (BUN)

  BUN is a waste product from protein breakdown that your kidneys clear from the blood, so it gives a rough read on kidney function and hydration.

  Men, 18+

  8–24 mg/dL

  Women, 18+

  6–21 mg/dL

• Creatinine

  Creatinine is a muscle waste product that your kidneys filter out, so the level in your blood is one of the main tools for checking kidney function.

  Men, 15+

  0.74–1.35 mg/dL

  Women, 16+

  0.59–1.04 mg/dL

• BUN/Creatinine Ratio

  A calculated comparison of your BUN with your creatinine that clinicians use as one clue to why a kidney-related number is high or low.

  Men, 18–59

  9–20 ratio

  Women, 18–59

  9–23 ratio

• Uric Acid

  Uric acid is a waste product from breaking down purines. High levels can lead to gout or kidney stones in some people.

  Men, 18+

  3.8–8.4 mg/dL

  Women, 18–50

  2.6–6.2 mg/dL

  Women, 51–70

  3–7.2 mg/dL

  Women, 71+

  3.1–7.9 mg/dL

• Calcium, Total

  Total calcium is the amount of calcium in your blood. It supports your nerves, muscles, heart and bones, and it is on most routine panels.

  18–59

  8.7–10.2 mg/dL

  Men, 60+

  8.6–10.2 mg/dL

  Women, 60+

  8.7–10.3 mg/dL

• Phosphorus (Phosphate)

  Phosphorus is a mineral that builds bones and powers cells. Its blood level mostly reflects your kidneys, parathyroid glands, vitamin D and diet.

  18+

  2.5–4.5 mg/dL

• Sodium

  Sodium is the main salt in your blood. This test shows how well your body balances water and salt.

  1+

  135–145 mmol/L

• Potassium

  Potassium is a mineral that helps your nerves, muscles and heart work. This test shows how much is in your blood.

  1+

  3.5–5.2 mmol/L

• Chloride

  Chloride is a salt mineral in your blood. It works with sodium to balance fluids and acid, and it is part of the basic and comprehensive metabolic panels.

  Adults

  96–106 mmol/L

• eGFR (Creatinine-based)

  An estimate of how well your kidneys filter blood, worked out from your creatinine, age and sex.

  18+

  60 and above mL/min/1.73 m²

Labs can include one more test in this panel that we haven’t written up yet.