Reference values vary based on several factors, including the specific laboratory that supplies them. A patient's blood test values should be interpreted based on the reference value of the laboratory in which the test was done; the laboratory typically provides these values with the test result. Representative values are listed in alphabetical order in the following table.
Representative Laboratory Reference Values: Blood, Plasma, and Serum
Test | Specimen | Conventional Units | SI Units |
|---|---|---|---|
Acetoacetate | Plasma | < 3 mg/L | < 0.3 mmol/L |
Acetylcholinesterase (AChE), red blood cells | Blood | 26.7–49.2 U/g Hb | 1.72–3.17 x 106 U/mol Hb |
Acid phosphatase (adults) | Serum | 0.5–5 U/L | 8–83 nkat/L |
Activated partial thromboplastin time (aPTT) | Plasma | 30–40 seconds | — |
Adrenocorticotropic hormone (ACTH) | Serum | 9–52 pg/mL (morning draw) | 2–11 pmol/L (morning draw) |
Albumin | Serum | 3.5–5.4 g/dL | 35–54 g/L |
Aldosterone: | |||
| Serum | 7–20 ng/dL | 194–554 pmol/L |
| Serum | 2–5 ng/dL | 55–138 pmol/L |
Alkaline phosphatase (ALP) | Serum | 36–150 U/L | 0.5–2.5 mckat/L |
Alpha-1 antitrypsin (AAT) | Serum | 100–273 mg/dL | 18–50 mcmol/L |
Alpha fetoprotein (AFP) | Serum | < 20 ng/mL | < 20 mcg/L |
Aminolevulinic acid, Delta (ALA) | Serum | 15–23 mcg/L | 1.14–1.75 mcmol/L |
Aminotransferase, alanine (ALT) | Serum | < 35 U/L | < 0.58 mckat/L |
Aminotransferase, aspartate (AST) | Serum | < 35 U/L | < 0.58 mckat/L |
Ammonia | Plasma | 40–80 mcg/dL | 23–47 mcmol/L |
Amylase | Serum | < 110 U/L | < 1.8 mckat/L |
Antibodies to extractable nuclear antigen (AENA) | Serum | < 20.0 units/mL | — |
Anti–cyclic citrullinated peptide (anti-CCP) antibodies | Serum | ≤ 20 units/mL | — |
Antidiuretic hormone (ADH; arginine vasopressin) | Plasma | < 1.7 pg/mL | < 1.57 pmol/L |
Anti–double-stranded DNA (dsDNA) antibodies, IgG | Serum | < 25 IU | — |
Antimitochondrial M2 antibodies | Serum | < 0.1 units | — |
Antineutrophil cytoplasmic antibodies (cANCA) | Serum | Negative | — |
Antinuclear antibodies (ANA) | Serum | ≤ 1.0 units | — |
Anti–smooth muscle antibodies (ASMA) titer | Serum | ≤ 1:80 | — |
Antistreptolysin O titer | Serum | < 150 units | — |
Antithyroid microsomal antibody titer | Serum | < 1:100 | — |
+Antitrypsin, Alpha-1 (AAT) | Serum | 83–199 mg/dL | 15.3–36.6 mcmol/L |
Apolipoproteins: | |||
| Serum | 98–210 mg/dL | 0.98–2.1 g/L |
| Serum | 88–180 mg/dL | 0.88–1.8 g/L |
| Serum | 44–148 mg/dL | 0.44–1.48 g/L |
| Serum | 55–151 mg/dL | 0.55–1.51 g/L |
Bicarbonate | Serum | 23–28 mEq/L | 23–28 mmol/L |
Bilirubin: | |||
| Serum | 0–0.3 mg/dL | 0–5.1 mcmol/L |
| Serum | 0.3–1.2 mg/dL | 5.1–20.5 mcmol/L |
Blood volumes (radioisotope labeling): | |||
| Blood | 28–43 mL/kg body wt | 0.028–0.043 L/kg body wt |
| Blood | 25–44 mL/kg body wt | 0.025–0.044 L/kg body wt |
| Blood | 20–30 mL/kg body wt | 0.02–0.03 L/kg body wt |
| Blood | 25–35 mL/kg body wt | 0.025–0.035 L/kg body wt |
Brain (B-type) natriuretic peptide (BNP) | Plasma | < 100 pg/mL | < 100 ng/L |
Calcitonin, age ≥ 16 years: | |||
| Serum | < 8 pg/mL | < 8ng/L |
| Serum | < 16 pg/mL | < 16 ng/L |
Calcium | Serum | 9–10.5 mg/dL | 2.2–2.6 mmol/L |
Cancer antigen (CA): | |||
| Serum | < 35 U/mL | < 35 kU/L |
| Serum | < 30 U/mL | < 30 kU/L |
Carbon dioxide (CO2) content | Serum | 23–28 mEq/L | 23–28 mmol/L |
Carbon dioxide partial pressure (PCO2) | Blood | Arterial: 35–45 mm Hg Venous: 38–50 mm Hg | Arterial: 4.7–6.0 kPa Venous: 5.1–6.7 kPa |
Carboxyhemoglobin | Plasma | 0.5–5% | — |
Carcinoembryonic antigen (CEA) | Serum | < 3 ng/mL Patients who smoke: < 5 ng/mL | < 3 mcg/L Patients who smoke: < 5 mcg/L |
Carotene | Serum | 75–300 mcg/dL | 1.4–5.6 mcmol/L |
CD4:CD8 ratio | Blood | 1.0–4.0 | — |
CD4+ T-cell count | Blood | 640–1175/mcL | 0.64–1.18 x 109/L |
CD8+ T-cell count | Blood | 335–875/mcL | 0.34–0.88 x 109/L |
Ceruloplasmin | Serum | 14–40 mg/dL | 0.93–2.65 mcmol/L |
Chloride | Serum | 98–106 mEq/L | 98–106 mmol/L |
Cholesterol, desirable level: | |||
| Plasma | ≥ 40 mg/dL | ≥ 1.04 mmol/L |
| Plasma | ≤ 130 mg/dL | ≤ 3.36 mmol/L |
Total (TC) | Plasma | 150–199 mg/dL | 3.88–5.15 mmol/L |
Coagulation factors: | |||
| Plasma | 150–300 mg/dL | 1.5–3.5 g/L |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
| Plasma | 60–150% of normal | — |
Complement: | |||
| Serum | 90–180 mg/dL | 0.9–1.8 g/L |
| Serum | 10–40 mg/dL | 0.10–0.40 g/L |
Total (CH50) | Serum | 30–75 U/mL | 30–75 kU/L |
Copper | Serum | 70–155 mcg/L | 11–24.3 mcmol/L |
Cortisol: | |||
| Serum | > 18 mcg/dL and usually ≥ 8 mcg/dL above baseline | > 498 nmol/L and usually ≥ 221 nmol/L above baseline |
| Serum | 3–13 mcg/dL | 83–359 nmol/L |
| Serum | 8–20 mcg/dL | 251–552 nmol/L |
| Serum | < 5 mcg/dL | < 138 nmol/L |
C-peptide | Serum | 0.9–4.3 ng/mL | 297–1419 pmol/L |
C-reactive protein (CRP) | Serum | < 0.8 mg/dL | < 8.0 mg/L |
C-reactive protein, highly sensitive (hsCRP) | Serum | < 0.2 mg/dL | < 2.0 mg/L |
Creatine kinase (CK) | Serum | 30–170 U/L | 0.5–2.83 mckat/L |
Creatinine | Serum | Men: 0.7–1.2 mg/dL Women: 0.5–1.0 mg/dL | Men: 60–110 mcmol/L Women: 45–90 mcmol/L |
D-dimer | Plasma | ≤ 500 ng/mL FEU (Fibrinogen Equivalent Units) | < 3 nmol/L FEU |
Dehydroepiandrosterone sulfate (DHEA-S): | |||
| Plasma | 0.6–3.3 mg/mL | 1.6–8.9 mcmol/L |
| Plasma | 1.3–5.5 mg/mL | 3.5–14.9 mcmol/L |
Delta-aminolevulinic acid (ALA) | Serum | 15–23 mcg/L | 1.14–1.75 mcmol/L |
11-Deoxycortisol (DOC): | |||
| Plasma | > 7 mcg/dL | > 203 nmol/L |
| Plasma | < 5 mcg/dL | < 145 nmol/L |
D-Xylose level 2 hours after ingestion of 25 g of D-xylose | Serum | > 20 mg/dL | > 1.3 nmol/L |
Epinephrine, supine | Plasma | < 75 ng/L | < 410 pmol/L |
Erythrocyte sedimentation rate (ESR): | |||
| Blood | 0–20 mm/hour | 0–20 mm/hour |
| Blood | 0–15 mm/hour | 0–20 mm/hour |
Erythropoietin | Serum | 2.6–18.5 mIU/mL | 2.6–18.5 IU/L |
Estradiol, females: | |||
| Serum | 14–27 pg/mL | 50–100 pmol/L |
| Serum | 14–54 pg/mL | 50–200 pmol/L |
| Serum | 19–40 pg/mL | 70–150 pmol/L |
Estradiol, males | Serum | 10–30 pg/mL | 37–110 pmol/L |
Ferritin: | |||
| Serum | 30–200 ng/mL | 30–200 mcg/L |
| Serum | 30–300 ng/mL | 30–300 mcg/L |
Fetoprotein, Alpha (AFP) | Serum | < 8.4 ng/mL | < 8.4 mcg/L |
Fibrinogen | Plasma | 150–350 mg/dL | 1.5–3.5 g/L |
Folate (folic acid): | |||
| Blood | 160–855 ng/mL | 362–1937 nmol/L |
| Serum | 2.5–20 ng/mL | 5.7–45.3 nmol/L |
Follicle-stimulating hormone (FSH), females: | |||
| Serum | 5–20 mU/mL | 5–20 U/L |
| Serum | 30–50 mU/mL | 30–50 U/L |
| Serum | > 35 mU/mL | > 35 U/L |
Follicle-stimulating hormone (FSH), adult males | Serum | 5–15 mU/mL | 5–15 U/L |
Fructosamine (glycated protein) | Plasma | 200–285 mcmol/L | 200-285 mcmol/L |
Gamma-glutamyl transpeptidase (GGT) | Serum | Adult male: 8–61 U/L Adult female: 5–36 U/L | Adult male: 0.14–1.03 mckat/L Adult female:0.09–0.61 mckat/L |
Gastrin | Serum | 0–180 pg/mL | 0–180 ng/L |
Globulins: | Serum | 2.5–3.5 g/dL | 25–35 g/L |
| Serum | 0.2–0.4 g/dL | 2–4 g/L |
| Serum | 0.5–0.9 g/dL | 5–9 g/L |
| Serum | 0.6–1.1 g/dL | 6–11 g/L |
| Serum | 0.7–1.8 mcg/mL | 0.7–1.8 mg/L |
| Serum | 0.7–1.7 g/dL | 7–17 g/L |
Glucose: | |||
| Plasma | < 140 mg/dL | < 7.8 mmol/L |
| Plasma | 70–105 mg/dL | 3.9–5.8 mmol/L |
Glucose-6-phosphate dehydrogenase (G6PD) | Blood | 5–15 U/g Hb | 0.32–0.97 mU/ mol Hb |
Glutamyl transpeptidase, Gamma (GGT) | Serum | Adult male: 8–61 U/L Adult female: 5–36 U/L | Adult male: 0.14–1.03 mckat/L Adult female: 0.09–0.61 mckat/L |
Growth hormone: | |||
| Plasma | < 2 ng/mL | < 2 mcg/L |
| Plasma | > 7 ng/mL | > 7 mcg/L |
Haptoglobin | Serum | 30–200 mg/dL | 0.3–2 g/L |
Hematocrit: | |||
| Blood | 36–47% | — |
| Blood | 41–51% | — |
Hemoglobin: | |||
| Blood | 12–16 g/dL | 120–160 g/L |
| Blood | 14–17 g/dL | 140–170 g/L |
Hemoglobin A1C | Blood | 4.7–8.5% | — |
Hemoglobin electrophoresis, adults: | |||
| Blood | 95–98% | — |
| Blood | 2–3% | — |
| Blood | 0% | — |
| Blood | 0.8–2.0% | — |
| Blood | 0% | — |
Hemoglobin electrophoresis, Hb F in children: | |||
| Blood | 50–80% | — |
| Blood | 8% | — |
| Blood | 1–2% | — |
Homocysteine: | |||
| Plasma | 0.40–1.89 mg/L | 3–14 mcmol/L |
| Plasma | 0.54–2.16 mg/L | 4–16 mcmol/L |
Human chorionic gonadotropin (hCG), quantitative | Serum | < 5 mIU/mL | < 5 IU/L |
Immunoglobulins: | |||
| Serum | 70–300 mg/dL | 0.7–3.0 g/L |
| Serum | < 8 mg/dL | < 80 mg/L |
| Serum | 0.01–0.04 mg/dL | 0.1–0.4 mg/L |
| Serum | 640–1430 mg/dL | 6.4–14.3 g/L |
| Serum | 280–1020 mg/dL | 2.8–10.2 g/L |
| Serum | 60–790 mg/dL | 0.6–7.9 g/L |
| Serum | 14–240 mg/dL | 0.14–2.4 g/L |
| Serum | 11–330 mg/dL | 0.11–3.3 g/L |
| Serum | 20–140 mg/dL | 0.2–1.4 g/L |
Insulin, fasting | Serum | 2.6–24.9 mcIU/mL | 15.6–149.4 pmol/L |
International normalized ratio (INR): | |||
| Plasma | 2.0–3.0 | — |
| Plasma | 2.5–3.5 | — |
| Plasma | 3.0–3.5 | — |
Iron | Serum | Males: 50–150 mcg/dL Females: 35–145 mcg/dL | Males: 9.2–27.5 mcmol/L Females: 6.4–26.5 mcmol/L |
Iron-binding capacity, total (TIBC) | Serum | 250–460 mcg/dL | 45–82 mcmol/L |
Lactate dehydrogenase (LDH) | Serum | 60–160 U/L | 1–1.67 mckat/L |
Lactic acid, venous | Blood | 6–16 mg/dL | 0.67–1.8 mmol/L |
Lactose tolerance test | Plasma | > 15 mg/dL increase in plasma glucose level | > 0.83 mmol/L increase in plasma glucose level |
Lead | Blood | Pediatric patients: < 20 mcg/dL Adult patients: < 80 mcg/dL | Pediatric patients: < 0.97 mcmol/L Adult patients: < 3.86 mcmol/L |
Leukocyte alkaline phosphatase (LAP) score | Peripheral blood smear | 13–130/100/ polymorphonuclear (PMN) leukocyte neutrophils and bands | — |
Lipase | Serum | < 95 U/L | < 1.58 mckat/L |
Lipoprotein (a) [Lp(a)] | Serum | ≤ 10 mg/dL | < 13nmol/L |
Luteinizing hormone (LH), females: | |||
| Serum | 5–22 mU/mL | 5–22 U/L |
| Serum | 30–250 mU/mL | 30–250 U/L |
| Serum | > 30 mU/mL | > 30 U/L |
Luteinizing hormone, males | Serum | 3–15 mU/mL | 3–15 U/L |
Magnesium | Serum | 1.5–2.4 mg/dL | 0.62–0.99 mmol/L |
Manganese | Serum | 0.3–0.9 ng/mL | 5.5–16.4 nmol/L |
Mean corpuscular hemoglobin (MCH) | Blood | 28–32 pg | — |
Mean corpuscular hemoglobin concentration (MCHC) | Blood | 32–36 g/dL | 320–360 g/L |
Mean corpuscular volume (MCV) | Blood | 80–100 fL | — |
Metanephrines, fractionated: | |||
| Plasma | < 0.50 nmol/L | — |
| Plasma | < 0.90 nmol/L | — |
Methemoglobin | Blood | < 1.0% | — |
Methylmalonic acid (MMA) | Serum | ≤ 400 nmol/L | 47.2 ng/L |
Myoglobin: | |||
| Serum | 25–58 mcg/L | 1.4–3.5 nmol/L |
| Serum | 28–72 mcg/L | 1.6–4.1 nmol/L |
Norepinephrine, supine | Plasma | 50–440 pg/mL | 0.3–2.6 nmol/L |
N-Terminal propeptide of BNP (NT-proBNP) | Plasma | < 75 years: < 125 pg/mL ≥ 75 years: < 450 pg/mL | < 125 ng/L < 450 ng/L |
5'-Nucleotidase (5'NT) | Serum | 4–11.5 U/L | — |
Osmolality | Plasma | 275–295 mOsm/kg H2O | 275–295 mmol/ kg H2O |
Osmotic fragility test | Blood | Increased fragility if hemolysis occurs in > 0.5% sodium chloride Decreased fragility if hemolysis is incomplete in 0.3% sodium chloride | — |
Oxygen partial pressure (PO2) | Blood | Arterial: 80–100 mm Hg | 10.7–13.3 kPa |
Parathyroid hormone (PTH) | Serum | 10–65 pg/mL | 10–65 ng/L |
Parathyroid hormone–related peptide (PTHrP) | Plasma | < 2.0 pmol/L | — |
Partial thromboplastin time, activated (aPTT) | Plasma | 25–35 seconds | — |
pH | Blood | Arterial: 7.35–7.45 Venous: 7.32–7.43 | — — |
Phosphorus, inorganic | Serum | 3.0–4.5 mg/dL | 0.97–1.45 mmol/L |
Platelet count | Blood | 150–350 x 103/mcL | 150–350 x 109/L |
Platelet life span, using chromium-51 (51Cr) | — | 8–12 days | — |
Porphyrins | Plasma | ≤ 1.0 mcg/dL | ≤ 10 mcg/L |
Potassium | Serum | 3.5–5 mEq/L | 3.5–5 mmol/L |
Prealbumin (transthyretin) | Serum | 18–45 mg/dL | 180–450 mg/L |
Progesterone: | |||
| Serum | < 1 ng/mL | < 0.03 nmol/L |
| Serum | 3–30 ng/mL | 0.1–0.95 nmol/L |
Prolactin: | |||
| Serum | < 20 mcg/L | < 870 pmol/L |
| Serum | < 15 mcg/L | < 652 pmol/L |
Prostate-specific antigen, total (PSA-T) | Serum | 0–4 ng/mL | 0–4 mcg/L |
Prostate-specific antigen, ratio of free to total (PSA-F:PSA-T) | Serum | > 0.25 | — |
Protein C activity | Plasma | 67–131% | — |
Protein C resistance, activated ratio (APC-R) | Plasma | 2.2–2.6 | — |
Protein S activity | Plasma | 82–144% | — |
Protein, total | Serum | 6–7.8 g/dL | 60–78 g/L |
Prothrombin time (PT) | Plasma | 11–13 seconds | — |
Pyruvic acid | Blood | 0.08–0.16 mmol/L | — |
Red blood cell count | Blood | 4.2–5.9 x 106 cells/mcL | 4.2–5.9 x 1012 cells/L |
Red blood cell survival rate, using 51Cr | Blood | T1/2 = 28 days | — |
Renin activity, plasma (PRA), upright, in males and females aged 18–39 years: | |||
| Plasma | 2.9–24 ng/mL/hour | 2.9–24 mcg/L/hour |
| Plasma | 0.6 (or lower)–4.3 ng/mL/hour | 0.6 (or lower)–4.3 mcg/L/hour |
Reticulocyte count: | |||
| Blood | 0.5–1.5% | — |
| Blood | 23–90 x 103/mcL | 23–90 x 109/L |
Rheumatoid factor (RF), by nephelometry | Serum | < 20 IU/mL | < 20 kIU/L |
Sodium | Serum | 136–145 mEq/L | 136–145 mmol/L |
Testosterone (total), adults: | |||
| Serum | 20–75 ng/dL | 0.7–2.6 nmol/L |
| Serum | 300–1200 ng/dL | 10–42 nmol/L |
Thrombin time | Plasma | 18.5–24 seconds | — |
Thyroid iodine-123 (123I) uptake | — | 5–30% of administered dose at 24 hour | — |
Thyroid-stimulating hormone (TSH) | Serum | 0.5–5.0 mcIU/mL | 0.5–5.0 mIU/L |
Thyroxine (T4): | |||
| Serum | 0.9–2.4 ng/dL | 12–31 pmol/L |
| — | 4–11 | — |
| Serum | 5–12 mcg/dL | 64–155 nmol/L |
Transferrin | Serum | 200–360 mg/dL | 2.0–3.6 g/L |
Transferrin saturation | Serum | 20–50% | — |
Triglycerides (fasting) | Serum | Normal: < 150 mg/dL Borderline: 150–199 mg/dL High: 200–499 mg/dL Very high: ≥ 500 mg/dL | Normal: < 1.69 mmol/L Borderline: 1.69–2.25 mmol/L High: 2.26–5.64 mmol/L Very high: > 5.65 mmol/L |
Triiodothyronine (T3): | |||
| Serum | 25–35% | — |
| Serum | 70–195 ng/dL | 1.1–3.0 nmol/L |
Troponin I (Contemporary assay) | Plasma | < 0.04 ng/mL | < 0.04 mcg/L |
Troponin I, highly sensitive (hs-TnI) | Serum | Females: ≤ 10 ng/L Males: ≤ 15 ng/L | <1.0 mcg/L <1.5 mcg/L |
Troponin T (Contemporary assay) | Serum | ≤ 0.03 ng/mL | ≤ 0.03 mcg/L |
Troponin T, highly sensitive (hs-TnT) | Serum | Females: ≤ 10 ng/L Males: ≤ 15 ng/L | <1.0 mcg/L <1.5 mcg/L |
Urea nitrogen (BUN) | Serum | 8–20 mg/dL | 2.9–7.1 mmol/L |
Uric acid | Serum | 2.5–8 mg/dL | 0.15–0.47 mmol/L |
Vitamin B12 | Serum | 200–800 pg/mL | 148–590 pmol/L |
Vitamin C (ascorbic acid): | |||
| Blood | < 20 mg/dL | < 1136 mcmol/L |
| Blood | 0.4–1.5 mg/dL | 23–85 mcmol/L |
Vitamin D: | |||
| Serum | 25–65 pg/mL | 65–169 pmol/L |
| Serum | 15–80 ng/mL | 37–200 nmol/L |
White blood cell count | Blood | 4.5–11 x 103 cells/mcL | 4.5–11 x 109 cells/L |
Segmented neutrophils | 2.6–8.5 x 103 cells/mcL | 2.6–8.5 x 109 cells/L | |
Band neutrophils | 0–1.2 x 103 cells/mcL | 0–1.2 x 109 cells/L | |
Lymphocytes | 0.77–4.5 x 103 cells/mcL | 0.77–4.5 x 109 cells/L | |
Monocytes | 0.14–1.3 x 103 cells/mcL | 0.14–1.3 x 109 cells/L | |
Eosinophils | 0–0.55 x 103 cells/mcL | 0–0.55 x 109 cells/L | |
Basophils | 0–0.22 x 103 cells/mcL | 0–0.22 x 109 cells/L | |
Zinc | Serum | 66–110 mcg/dL | 10.1–16.8 mcmol/L |
*American Board of Internal Medicine: ABIM Laboratory Test Reference Ranges ̶ July 2021. Accessed 9/16/2021. | |||
mckat = microkatal; pkat = picokatal. | |||
