Laboratory Reference Ranges – Normal Lab Values

Laboratory testing involves the checking of blood, urine, and body tissue samples in order to see if the resulting lab values fall within the normal range. Lab values are used to determine a patient’s overall health and well-being.

There are many factors that can affect a patient’s result and lab values but some of the most common factors are gender, age, race, the medicines taken, and the presense of any underlying condition(s). Doctors will also advise patients to skip drinking, eating, and taking medication several hours before the test.

Lab values are used in diagnosis. Physicians will compare current lab values with previous results to determine changes in health and the effectiveness of treatment.

Standard Normal Lab Values : Complete Blood Count (CBC)

Blood is the most common type of biological fluid used for lab testing. Just 5 mL of blood is enough to perform a wide range of clinical tests.

Complete blood count or more often known by its acronym CBC is one of the most basic laboratory tests to assess medical conditions and health status of an individual. Results of this examination can help doctors diagnose infection and diseases. The lab values listed below indicates the normal range in a healthy adult for male or female.

Total Hemoglobin (Hgb or Hb)

Hemoglobin tests are performed as part of a complete CBC test. Hemoglobin are proteins in red blood cells that transmits oxygen to the body’s vital organs and transports carbon dioxide from organs to your lungs. Hemoglobin are high in iron, which means they are responsible for the bright red color of blood. Hemoglobin is often expressed in grams per deciliter (g/dL). A patient with low levels of hemoglobin has anemia.

Normal Range:

Female : 11-16 g/dL

Male: 14-18 g/dL

Child: 10-14 g/dL

Newborn: 15-25 g/dL

Red Blood Cells

The red blood cells act as the transport of oxygen and carbon dioxide from lungs towards body tissues (and vice versa). Red blood cells or erythrocyte count is measured in millions per cubic millimeter. A patient with low RBC count can have a condition called aplastic anemia. The following are the standard normal values for female, male, and child.

Normal Range

Female: 3.8 to 11.9 million/cu mm blood

Male: 3.8 to 11.0 million/cu mm blood

Child: 5.0 to 10.0 million/cu mm blood

White Blood Cells

White blood cell count is a test that measures the number of white blood cells in the body. A higher or lower number of WBC can indicate an underlying condition such as autoimmune diseases and blood disorders. It’s also used to check the effectiveness of chemotherapy for patients with cancer.

Normal Range

4500 to 11000 per microliter (4.5 to 11.0 × 109/L)

Hematocrit Hct

The hematocrit test is also part of the CBC test and is used to diagnose and monitor several medical conditions. It determines the percentage of blood blood that is composed of red blood cells. Patient results may vary depending on the structure, size, and number of their RBCs. A low or very high red blood cell count indicates a medical condition or disease.

Normal Range

Female: 34% – 47%

Male: 39% – 54%

Child: 30% – 42%

Newborn: 55% – 68%

Platelet Count 

Platelets or thrombocytes are cell fragments that are found in the bloodstream. They form a clot over damaged blood vessels. Measuring platelet count is important in checking for patient tendencies for bleeding and thrombosis.

Normal Range

150,000 to 400,000 per micro liter

Absolute neutrophil count: higher than  1500/μL (1.50 × 109/L)
Activated partial thromboplastin : 25 to 35 seconds
D-dimer: lower than 5 μg/mL (0.5 mg/L)
Erythrocyte : 4.2-5.9 × 106/μL
Erythrocyte sedimentation rate
Male: 0-15 mm/h
Female: 0-20 mm/h
Erythropoietin: 5-36 mU/mL
Haptoglobin, serum: 50-150 mg/dL

General Chemistry and Serum

Blood chemistry set is used to measure the amount of substances in the body. Glucose measures our blood sugar and determines if the patient is within the criterion for diabetes. Uric acid is often an indication of kidney stones and a high BUN and creatinine suggest impairment in our kidney. In general, the basic chemistry helps us assess many conditions and give light to how the body’s organs are working.

Normal Range:

Albumin: 3.5-5.5 g/dL

Alkaline Phosphate (ALP): L32 – 110 IU/L

Aminotransferase, alanine (ALT): 0-35 U/L

Aminotransferase, aspartate (AST): 0-35 U/L

Ammonia, plasma: 40-80 μg/dL

Amylase, serum: 0-130 U/L

Bilirubin: <1.0 mg/dL

Bicarbonate (CO2): 23-29 mEq/L

Blood Urea Nitrogen (BUN): 7-2 mg/dL

Ferritin: 10 – 350 NG/ML

Chloride (Cl): 96-112 mEq/L

Glucose: 65-99 mg/dL

Magnesium (Mg): 1.5-2. mEq/L

Potassium (K):  3.5-5.5 mEq/L

Phosphorus: 2.5-4.5mg/dL

Sodium (Na): 135-148 mEq/L

Calcium (Ca) 8.5 to 10.2 mg/dL

Calcium Phosphate Product (Ca x PO4): 0 – 70

Creatinine (Cr)(Male): 0.2-0.6 mg/dL

Creatinine (Cr)(Female): 0.6 – 1.0mg/dL

Triglyceride: 40-50 mg/dL

Total Cholesterol:130-200 mg/dL

C3: 55-120 mg/dL

C4: 10-40 mg/dL

C-reactive protein, blood: 0-0.8 mg/dL

Fibrinogen, plasma: 150-350 mg/dL

Folate, serum: 4.0-20 ng/mL

Glucose, plasma: fasting, 70-100 mg/dL

γ-Glutamyltransferase, serum: 0-30 U/L


Immunoglobulins or antibodies are molecules produced by white blood cells. They function as the primary part of the immune response by determining and binding to antigens, such as viruses and bacteria. viruses,

Globulins, total: 2.5-3.5 g/dL
IgG: 640-1430 mg/dL
IgA: 70-300 mg/dL
IgM: 20-140 mg/dL
IgD: less than 8 mg/dL
IgE: 0-90 U/mL

Iron studies
Ferritin, serum: 15-200 ng/mL
Iron, serum: 60-160 μg/dL
Transferring saturation: 20%-50%

Lactate dehydrogenase, serum: 60-100 U/L
Lactate, plasma: 0.5-1.6 mEq/L
Lipase, serum: 13-60 U/L
Magnesium, serum: 1.5-2.4 mg/dL
Phosphate, alkaline, serum: 36-92 U/L
Phosphorus, serum: 3.0-4.5 mg/dL
Prostate-specific antigen, serum: less than 4

Protein, serum
Total: 6.0-7.8 g/dL
Albumin: 3.5-5.5 g/dL
Globulins, total: 2.5-3.5 g/dL

Rheumatoid factor: less than 40 U/mL
Triglycerides: less than 150 mg/dL , desirable
Troponin T: 0-0.1 ng/mL
Vitamin B12, serum: 200-800 pg/mL


Coagulation is a test that measures a patient’s blood’s ability to clot. It also determines the time it takes to clot. This test helps doctors assess risk of excessive bleeding and developing clots in the  blood vessels. A longer prothrombin time can mean a prolonged liver disease or surgical trauma associated with blood loss. A low platelet count can mean leukemia or a severe hemorrhage.

Normal Range:

Activated clotting time (ACT): 90 to 130 seconds

Activated partial thromboplastin time (APT):  21 to 35 seconds

Partial Thromboplastin Time (PTT):  32 to 45 seconds

Platelets: 140,000 to 450,000 /ml

Plasminogen: 62% to 130%

Prothrombin time (PT) 10 to 14 seconds

Thrombin time 11 – 15 seconds

FDP levels: less than 10 µg/dL

Fibrinogen: 160 to 450 mg/dL

Normal bleeding time: 3 to 7 minutes

Arterial Lab Values

Normal Range: 

pH: 7.35 – 7.45

Partial Pressure of Oxygen (PaO2): 85 to 100 mm Hg

Partial Pressure of Carbon Dioxide (PaCO2): 35 to 45 mm Hg

Bicarbonate (HCO3): 22 to 26 mEq/L

Oxygen saturation:  96% to 100%


Venous Lab Values 

Normal Range: 

pH: 7.31 – 7.41

Partial Pressure of Oxygen (PaO2): 30 to 40 mm Hg

Partial Pressure of Carbon Dioxide (PaCO2): 41 to 51  mm Hg

Bicarbonate (HCO3): 22 to 29 mEq/L

Oxygen saturation:  60% to 85%

Hemodynamic Parameters 

Hemodynamic monitoring focuses on the measurement of blood pressure in veins, heart, and arteries. This test is conducted to determine a patient’s heart health through the flow of blood and the amount of oxygen present in the blood.

Normal Range:

Arterial Blood Pressure (BP): 90 to 140 mmHg

Diastolic (DBP): 60 to 90 mmHg

Mean Arterial Pressure (MAP): 70 to 105 mmHg

Left Atrial Pressure (LAP): 4 to 12 mmHg

Right Atrial Pressure (RAP): 4 to 6 mmHg

Cardiac Output (CO) 4.0 to 8.0 l/min

Cardiac Index (CI) 2.5 to 4.0 l/min/m2

Stroke Volume Index (SVI) 33 to 47 ml/m2/beat

Systemic Vascular Resistance (SVR): 900 to 1600 dynes sec/cm5

Systemic Vascular Resistance Index (SVRI):1970 – 2390 dynes sec/cm5/m2

Pulmonary Vascular Resistance (PVR): 155 to 255 dynes sec/cm5

Pulmonary Vascular Resistance Index (PVRI): 255 to 285 dynes sec/cm5/m2

Lipoproteins & Triglycerides

Total: <200mg/dL

AST: <40U/L

ALP: 42-128U/L

ALT: <40U/L

HDL: >60mg/dL

LDL: <70mg/dL

Triglycerides: <150mg/dL


Urine is another commonly used fluid for lab testing. It’s the most suitable sample for evaluating kidney functions.

Urine analysis is the test used to evaluate urine samples. This diagnostic examination is important in diagnosing certain illnesses including diabetes mellitus and chronic nephritis. Urinalysis often involves three stages, the first is the visual exam, followed by the dipstick test, and lastly the microscopic exam. When doing a urinalysis, best practice is to use the first morning urine sample of a patient.


Normal urine should be clear yellow.

normal lab values in adults
Normal lab values in adults

A cloudy urine may indicate urates, phosphates or the presence of RBC or WBC.

Foamy urine can be the result of protein or bile acids in the urine.

Urine color that ranges from red orange, blue green, to brown black can also be a result of certain medications such as rifampin, elavil, clorets abuse, iron salts, and Flagyl.


Normal ph levels should be from 4.5 to 8.

An acidic urine can deter bacterial colonization while a urine high in Alkaline can be caused by tubular defects.

Protein content in Urine

The normal protein content should be 0- +1 or less than 150mg/day

High protein content in urine can be an indication of one the following conditions: high blood pressure, lupus nephritis, diabetic nephropathy, hemolysis or multiple myeloma.

Microscopic analysis of Urine 

Urine must be sterile and should have a few cells, crystals, and bacteria.

Except during menstrual period, there should be no red blood cells present in urine.

White blood cells in urine indicate an infection in the body.

Bacteria are common in urine but a significant number may be an indication of infection.

Crystals in the form of phosphate, oxalate, and amorphous phosphate are present in the urine of a healthy person.

Neurological Lab Values 

Normal Range:

Cerebral Perfusion Pressure (CPP): 70 to 90 mm Hg

Intracranial Pressure (ICP): 7 to 15 mmHg