Lab test reference
All 117 lab tests
Reference ranges in both unit systems, with critical values, causes, and nursing notes. Search a test, browse by panel, or jump to the unit converter.
Complete Blood Count (CBC)
16 tests · Red cells, white cells, platelets, and the red-cell indices used to classify anemia and infection.
Absolute Neutrophil Count (ANC)2500–7000 cells/µL · 2.5–7 10⁹/LHas critical valueBasophils (%)0–1 % of WBC · 0–0.01 fractionEosinophils (%)1–4 % of WBC · 0.01–0.04 fractionHematocrit (Hct)36–52 % · 0.36–0.52 proportion of 1.0Has critical valueHemoglobin (Hgb)12–17.5 g/dL · 120–175 g/LHas critical valueLymphocytes (%)20–40 % of WBC · 0.2–0.4 fractionMean Corpuscular Hemoglobin (MCH)27–33 pg/cell · 27–33 pgMean Corpuscular Hemoglobin Concentration (MCHC)32–36 g/dL · 320–360 g/LMean Corpuscular Volume (MCV)80–100 fLMonocytes (%)2–8 % of WBC · 0.02–0.08 fractionNeutrophils (%)40–70 % of WBC · 0.4–0.7 fractionPlatelet Count150–400 10³/µL · 150–400 10⁹/LHas critical valueRed Blood Cell Count (RBC)4.2–5.9 10⁶/µL · 4.2–5.9 10¹²/LRed Cell Distribution Width (RDW)11.5–14.5 %Reticulocyte Count0.5–2.5 % of RBC · 0.005–0.025 fractionWhite Blood Cell Count (WBC)4.5–11 10³/µL · 4.5–11 10⁹/LHas critical value
Electrolytes & Minerals
9 tests · Sodium, potassium, chloride, bicarbonate, calcium, magnesium, and phosphate — the core of the BMP.
Anion Gap8–16 mEq/L · 8–16 mmol/LBicarbonate (CO₂ content)22–29 mEq/L · 22–29 mmol/LHas critical valueCalcium, Ionized4.6–5.3 mg/dL · 1.15–1.33 mmol/LHas critical valueCalcium, Total (Ca²⁺)8.6–10.2 mg/dL · 2.15–2.55 mmol/LHas critical valueChloride (Cl⁻)98–106 mEq/L · 98–106 mmol/LHas critical valueMagnesium (Mg²⁺)1.6–2.6 mg/dL · 0.66–1.07 mmol/LHas critical valuePhosphate (Phosphorus)2.5–4.5 mg/dL · 0.81–1.45 mmol/LHas critical valuePotassium (K⁺)3.5–5 mEq/L · 3.5–5 mmol/LHas critical valueSodium (Na⁺)135–145 mEq/L · 135–145 mmol/LHas critical value
Kidney Function
5 tests · BUN, creatinine, eGFR, and uric acid — how the kidneys are filtering.
Blood Urea Nitrogen (BUN)7–20 mg/dL · 2.5–7.1 mmol/L (urea)Has critical valueBUN-to-Creatinine Ratio10–20 ratioCreatinine, Serum0.6–1.3 mg/dL · 53–115 µmol/LHas critical valueEstimated GFR (eGFR)≥ 90 (normal kidney function) mL/min/1.73 m² · ≥ 90 mL/min/1.73 m²Has critical valueUric Acid3.4–7 mg/dL · 202–416 µmol/L
Glucose & Diabetes
5 tests · Fasting and random glucose, HbA1c, the glucose tolerance test, and C-peptide.
Liver Function (LFTs)
9 tests · Transaminases, alkaline phosphatase, bilirubin, albumin, protein, and ammonia.
Alanine Aminotransferase (ALT)7–56 U/L · 0.12–0.93 µkat/LAlbumin, Serum3.5–5 g/dL · 35–50 g/LAlkaline Phosphatase (ALP)44–147 U/L · 0.73–2.45 µkat/LAmmonia15–45 µg/dL · 11–32 µmol/LAspartate Aminotransferase (AST)10–40 U/L · 0.17–0.67 µkat/LBilirubin, Direct (Conjugated)0–0.3 mg/dL · 0–5.1 µmol/LBilirubin, Total0.3–1.2 mg/dL · 5.1–20.5 µmol/LHas critical valueGamma-Glutamyl Transferase (GGT)8–61 U/L · 0.13–1.02 µkat/LTotal Protein6–8.3 g/dL · 60–83 g/L
Lipid Panel
5 tests · Total, LDL, and HDL cholesterol, triglycerides, and VLDL for cardiovascular risk.
Cholesterol, Total< 200 desirable mg/dL · < 5.2 desirable mmol/LHDL Cholesterol≥ 40 (higher is protective) mg/dL · ≥ 1.0 mmol/LLDL Cholesterol< 100 optimal mg/dL · < 2.6 optimal mmol/LTriglycerides< 150 normal mg/dL · < 1.7 normal mmol/LHas critical valueVLDL Cholesterol2–30 mg/dL · 0.05–0.78 mmol/L
Thyroid Function
6 tests · TSH, free and total T4/T3, and thyroid antibodies.
Free Thyroxine (Free T4)0.8–1.8 ng/dL · 10–23 pmol/LFree Triiodothyronine (Free T3)2.3–4.2 pg/mL · 3.5–6.5 pmol/LThyroid Peroxidase Antibody (TPO Ab)< 35 (negative) IU/mL · < 35 kIU/LThyroid-Stimulating Hormone (TSH)0.4–4 mIU/LTotal Thyroxine (Total T4)5–12 µg/dL · 64–154 nmol/LTotal Triiodothyronine (Total T3)80–200 ng/dL · 1.2–3.1 nmol/L
Coagulation Studies
7 tests · PT/INR, aPTT, fibrinogen, and D-dimer for bleeding and clotting.
Activated Partial Thromboplastin Time (aPTT)25–35 secondsHas critical valueBleeding Time2–7 minutesD-Dimer< 0.5 (negative) µg/mL FEU · < 0.5 mg/L FEUFibrinogen200–400 mg/dL · 2–4 g/LHas critical valueInternational Normalized Ratio (INR)0.8–1.1 (off anticoagulation) ratio · 0.8–1.1 ratioHas critical valueProthrombin Time (PT)11–13.5 secondsHas critical valueThrombin Time14–19 seconds
Arterial Blood Gas (ABG)
6 tests · pH, PaCO₂, PaO₂, bicarbonate, and saturation for acid–base and oxygenation.
Arterial pH7.35–7.45 pH unitsHas critical valueBase Excess-2–2 mEq/L · -2–2 mmol/LHCO₃⁻ (Arterial Bicarbonate)22–26 mEq/L · 22–26 mmol/LHas critical valuePaCO₂ (Arterial CO₂)35–45 mm Hg · 4.7–6 kPaHas critical valuePaO₂ (Arterial O₂)80–100 mm Hg · 10.6–13.3 kPaHas critical valueSaO₂ (Arterial Oxygen Saturation)95–100 % · 0.95–1 fractionHas critical value
Urinalysis
11 tests · Specific gravity, pH, protein, glucose, ketones, and the microscopic exam.
Leukocyte EsteraseNegativeUrine BilirubinNegativeUrine Blood (RBC / Hematuria)0–3 RBC/hpfUrine GlucoseNegativeUrine KetonesNegativeUrine NitritesNegativeUrine pH4.6–8 pH unitsUrine ProteinNegative to traceUrine Specific Gravity1.005–1.03Urine Urobilinogen0.1–1 mg/dL · 1.7–17 µmol/LUrine WBC (Leukocytes)0–5 WBC/hpf
Cardiac Markers
7 tests · Troponin, CK-MB, myoglobin, and the natriuretic peptides.
B-type Natriuretic Peptide (BNP)< 100 (heart failure unlikely) pg/mL · < 100 ng/LCK-MB< 5 (or < 5% of total CK) ng/mL · < 5 µg/LCreatine Kinase (CK)30–200 U/L · 0.5–3.34 µkat/LHas critical valueMyoglobin25–72 ng/mL · 25–72 µg/LNT-proBNP< 125 (age < 75); < 450 if older pg/mL · < 125 ng/LTroponin I< 0.04 (assay-dependent) ng/mL · < 0.04 µg/LHas critical valueTroponin T< 0.01 (assay-dependent) ng/mL · < 0.01 µg/LHas critical value
Iron Studies
5 tests · Serum iron, ferritin, TIBC, transferrin, and saturation for anemia workups.
Tumor Markers
7 tests · PSA, CEA, CA-125, CA 19-9, AFP, and more — for monitoring, not screening (education only).
Alpha-Fetoprotein (AFP)< 10 (nonpregnant adult) ng/mL · < 10 µg/LBeta-hCG (Tumor Marker)< 5 (nonpregnant) mIU/mL · < 5 IU/LCA 15-3< 30 U/mL · < 30 kU/LCA 19-9< 37 U/mL · < 37 kU/LCA-125< 35 U/mL · < 35 kU/LCarcinoembryonic Antigen (CEA)< 3.0 nonsmoker (< 5.0 smoker) ng/mL · < 3.0 µg/LProstate-Specific Antigen (PSA)< 4.0 (age-dependent) ng/mL · < 4.0 µg/L
Therapeutic Drug Levels
9 tests · Digoxin, lithium, phenytoin, vancomycin, and other drugs with narrow therapeutic windows.
Acetaminophen Level10–30 (therapeutic) µg/mL · 66–199 µmol/LHas critical valueCarbamazepine Level4–12 µg/mL · 17–51 µmol/LHas critical valueDigoxin Level0.8–2 ng/mL · 1–2.6 nmol/LHas critical valueLithium Level0.6–1.2 mEq/L · 0.6–1.2 mmol/LHas critical valuePhenytoin Level10–20 µg/mL · 40–79 µmol/LHas critical valueSalicylate Level15–30 (anti-inflammatory) mg/dL · 1.1–2.2 mmol/LHas critical valueTheophylline Level10–20 µg/mL · 56–111 µmol/LHas critical valueValproic Acid Level50–100 µg/mL · 347–693 µmol/LHas critical valueVancomycin Trough10–20 µg/mL · 7–14 µmol/LHas critical value
Inflammatory & Other Chemistry
10 tests · CRP, ESR, procalcitonin, lactate, pancreatic enzymes, osmolality, and key vitamins.
Amylase30–110 U/L · 0.5–1.84 µkat/LC-Reactive Protein (CRP)< 1.0 (varies) mg/dL · < 10 mg/LErythrocyte Sedimentation Rate (ESR)≤ 20 (age/sex-dependent) mm/hr · 0–20 mm/hrFolate (Folic Acid)3–17 ng/mL · 7–39 nmol/LLactate (Lactic Acid)0.5–2.2 mmol/LHas critical valueLipase0–160 U/L · 0–2.67 µkat/LOsmolality, Serum275–295 mOsm/kg · 275–295 mmol/kgHas critical valueProcalcitonin< 0.10 (bacterial infection unlikely) ng/mL · < 0.10 µg/LVitamin B12 (Cobalamin)200–900 pg/mL · 148–664 pmol/LVitamin D, 25-Hydroxy30–100 sufficient (< 20 deficient) ng/mL · 75–250 nmol/L