Current metric units Conversion factor = SI units SI units Conversion factor = Current metric units |
Test | Specimen | Conventional Units | Conversion Factor | SI Units2 | Collection |
Acetaminophen | Serum | 10-20 mg/L Panic: > 50 mg/L | 66.16 | 66-132 mcmol/L | Serum separator tube (SST) |
Acetoacetate | Serum or urine | Negative | | Negative | SST or urine container |
Adrenocorticotropic hormone (ACTH) | Plasma | 9-52 pg/mL (laboratory-specific) | 0.22 | 2-11 pmol/L | Siliconized glass or plastic lavender |
Alanine aminotransferase (ALT, SGPT, GPT) | Serum | 7-56 units/L (laboratory-specific) | 0.02 | 0.14-1.12 mckat/L (laboratory-specific) | SST |
Albumin | Serum | 3.4-4.7 g/dL | 10.00 | 34-47 g/L | SST |
Aldosterone | Serum | Salt-loaded (120 mEq Na+/d): | 27.74 | | SST |
Supine: 3-10 ng/dL | 83-277 pmol/L |
Upright: 5-30 ng/dL | 139-831 pmol/L |
Salt-depleted (20 mEq Na+/d): | |
Supine: 12-36 ng/dL | 332-997 pmol/L |
Upright: 17-137 ng/dL | 471-3795 pmol/L |
Urine | Salt-loaded (120 mEq Na+/d for 3-4 days): 1.5-12.5 mcg/24 h | 2.77 | 4.2-34.6 nmol/d | Boric acid |
Salt-depleted (20 mEq Na+/d for 3-4 days): 18-85 mcg/24 h | 49.9-235.5 nmol/d |
Alkaline phosphatase | Serum | 41-133 units/L (method- and age-dependent) | 0.02 | 0.7-2.2 mckat/L (method- and age-dependent) | SST |
Ammonia (NH3) | Plasma | 18-60 mcg/dL | 0.59 | 11-35 mcmol/L | Green (iced) |
Amylase | Serum | 20-110 units/L (laboratory-specific) | 0.02 | 0.33-1.83 mckat/L (laboratory-specific) | SST |
Angiotensin-converting enzyme (ACE) | Serum | 12-35 units/L (method-dependent) | 16.67 | < 590 nkat/L (method-dependent) | SST |
Antithrombin III (AT III) | Plasma | 84-123% (qualitative)22-39 mg/dL (quantitative) | | | Blue |
1-Antitrypsin | Serum | 110-270 mg/dL | 0.01 | 1.1-2.7 g/L | SST |
Aspartate aminotransferase (AST, SGOT, GOT) | Serum | 0-35 units/L (laboratory-specific) | 0.02 | 0-0.58 mckat/L (laboratory-specific) | SST |
Basophil count | Whole blood | 0.01-0.12 103/mcL | 1.00 | 0.01-0.12 109/L | Lavender |
Bilirubin | Serum | Total: 0.1-1.2 mg/dL Direct (conjugated to glucuronide): 0.1-0.5 mg/dL Indirect (unconjugated): 0.1-0.7 mg/dL | 17.10 | 2-21 mcmol/L < 8 mcmol/L < 12 mcmol/L | SST |
Blood urea nitrogen (BUN) | Serum | 8-20 mg/dL | 0.36 | 2.9-7.1 mmol/L | SST |
-Natriuretic peptide | Whole blood | < 50 pg/mL | | | Lavender |
C-peptide | Serum | 0.8-4.0 ng/mL | 1.00 | 0.8-4.0 mcg/L | Iced (fasting) Gold SST |
C-reactive protein | Serum | < 5 mg/L | 1.00 | < 5 mg/L | SST |
Calcitonin | Plasma | Male: 0-11.5 pg/mL Female: 0-4.6 pg/mL | 1.00 | Male: 0-11.5 ng/L Female: 0-4.6 ng/L | Green Gold SST |
Calcium (Ca2+) | Serum | 8.5-10.5 mg/dL Panic: < 6.5 or > 13.5 mg/dL | 0.25 | 2.1-2.6 mmol/L | SST |
Calcium (ionized) | Serum | 4.6-5.3 mg/dL | 0.25 | 1.15-1.32 mmol/L | Green (anaerobic) |
Calcium (UCa) | Urine | 100-300 mg/d | 0.025 | 2.5-7.5 mmol/d | Urine bottle containing hydrochloric acid |
Carbon dioxide, partial pressure (Pco2) | Whole blood | 32-48 mm Hg | 0.13 | 4.26-6.38 kPa | Heparinized syringe (iced) |
Carbon dioxide (CO2), total (bicarbonate) | Serum | 22-32 mEq/L Panic: < 15 or > 40 mEq/L | 1.00 | 22-32 mmol/L Panic: < 15 or > 40 mmol/L | SST |
Carboxyhemoglobin (HbCO) | Whole blood | < 9% of total hemoglobin (Hb) | 0.01 | < 0.09 fraction of total hemoglobin | Green |
Carcinoembryonic antigen (CEA) | Serum | 0-5 ng/mL | 1.00 | 0-5 mcg/L | SST |
CD4 T cell count | Whole blood | 359-1725 cells/mcL | | | Lavender (complete blood count and differential and % CD4 required) |
Ceruloplasmin | Serum | 20-60 mg/dL (laboratory-specific) | 10.00 | 200-600 mg/L | SST |
Chloride (Cl-) | Serum | 101-112 mEq/L | 1.00 | 101-112 mmol/L | SST |
Cholesterol | Serum | Desirable: < 200 mg/dL Borderline: 200-239 mg/dL High risk: > 240 mg/dL | 0.03 | Desirable: < 5.2 mmol/L Borderline: 5.2-6.1 mmol/L High risk: > 6.2 mmol/L | SST |
Chorionic gonadotropin, -subunit ( -hCG), quantitative | Serum | Males and nonpregnant females: undetectable or < 5 mU/mL | 1.00 | Males and nonpregnant females: undetectable or < 5 units/L | SST |
Complement C3 | Serum | 64-166 mg/dL | 10.00 | 640-1660 mg/L | SST |
Complement C4 | Serum | 15-45 mg/dL | 10.00 | 150-450 mg/L | SST |
Complement CH50 | Serum | (Laboratory-specific) | | | Red |
Cortisol | Serum | 8:00 AM: 5-20 mcg/dL | 27.59 | 140-550 nmol/L | SST |
Cortisol (urinary free) | Urine | 10-110 mcg/24 h | 2.76 | 30-300 nmol/d | Urine bottle containing boric acid |
Creatine kinase (CK) | Serum | 32-267 units/L (method-dependent) | 0.02 | 0.53-4.45 mckat/L (method-dependent) | SST |
Creatine kinase MB (CKMB) | Serum | < 16 units/L or < 4% of total CK (laboratory-specific) Mass units: 0-7 mcg/L | 0.04 | < 0.27 mckat/L | SST |
Creatinine (Cr) | Serum | 0.6-1.2 mg/dL | 83.3 | 50-100 mcmol/L | SST |
Creatinine clearance (ClCr) | See Collection column. | Adults: 90-140 mL/min/1.73 m2 body surface area (BSA) | 0.017 | 1.5-2.3 mL/s/1.73 m2 BSA | Carefully timed 24-hour urine and simultaneous serum or plasma creatinine sample |
Cryoglobulins | Serum | < 0.12 mg/dL | | | Red (at 37 C) |
Eosinophil count | Whole blood | 0.04-0.5 103/mcL | 1.00 | 0.04-0.5 109/L | Lavender |
Erythrocyte count (RBC count) | Whole blood | 4.7-6.1 106/mcL | 1.00 | 4.7-6.1 1012/L | Lavender |
Erythrocyte sedimentation rate | Whole blood | Male: < 10 mm/h Female: < 15 mm/h (laboratory-specific) | | Same | Lavender |
Erythropoietin (EPO) | Serum | 5-20 mU/mL | 1.00 | 5-20 units/L | SST |
Ethanol | Serum | mg/dL Legal driving under the influence in many states is defined as > 80 mg/dL (> 17 mmol/L) blood alcohol level; serum alcohol levels are 10-35% higher than blood alcohol levels | 0.217 | mmol/L | SST |
Factor VIII assay | Plasma | 40-150% of normal (varies with age) | | | Blue |
Fecal fat | Stool | Random: < 60 droplets of fat per high-power field72-hour: < 7 g/d | | | Qualitative: Random stool sample Quantitative: 72-hour collection following 2-day dietary fat regimen |
Ferritin | Serum | Male: 16-300 ng/mL Female: 4-161 ng/mL | 1.00 | Male: 16-300 mcg/L Female: 4-161 mcg/L | SST |
-Fetoprotein (AFP) | Serum | 0-15 ng/mL | 1.00 | 0-15 mcg/L | SST |
Fibrin D-dimers | Plasma | Negative | | | Blue |
Fibrinogen (functional) | Plasma | 175-433 mg/dL Panic: < 75 mg/dL | 0.01 | 1.75-4.3 g/L | Blue |
Folic acid (red cells) | Whole blood | 165-760 ng/mL | 2.27 | 370-1720 nmol/L | Lavender |
Follicle-stimulating hormone (FSH) | Serum | Female: | 1.00 | Female: | SST |
Follicular phase 4-13 mU/mL | 4-13 units/L |
Luteal phase 2-13 mU/mL | 2-13 units/L |
Midcycle 5-22 mU/mL | 5-22 units/L |
Postmenopausal 30-138 mU/mL | 30-138 units/L |
Male: 1-10 mU/mL (laboratory-specific) | Male: 1-10 units/L (laboratory-specific) |
Free erythrocyte protoporphyrin (FEP) | Whole blood | < 35 mcg/dL (method-dependent) | | | Lavender |
Fructosamine | Serum | | | 190-270 mcmol/L | SST |
-Glutamyltranspeptidase (GGT) | Serum | 9-85 units/L (laboratory-specific) | 0.02 | 0.15-1.42 mckat/L (laboratory-specific) | SST |
Gastrin | Serum | < 100 pg/mL (laboratory-specific) | 1.00 | < 100 ng/L | SST |
Glucose | Serum | 60-110 mg/dL Panic: < 40 or > 500 mg/dL | 0.055 | 3.3-6.1 mmol/L | (Fasting) SST |
Glucose-6-phosphate dehydrogenase (G6PD) screen | Whole blood | 5-14 units/g Hb | 0.02 | 0.1-0.28 mckat/L | Lavender |
Glutamine | Cerebrospinal fluid (CSF) | 6-15 mg/dL Panic: > 40 mg/dL | 68.5 | 411-1028 mcmol/L | Collect CSF in a plastic tube |
Glycated (glycosylated) hemoglobin (HbA1c) | Serum | 3.9-6.9% (method-dependent) | | | Lavender |
Growth hormone (GH) | Serum | 0-5 ng/mL | 1.00 | 0-5 mcg/L | SST |
Haptoglobin | Serum | 46-316 mg/dL | 0.01 | 0.5-3.2 g/L | SST |
HDL cholesterol | Serum | Male: 27-67 mg/dL Female: 34-88 mg/dL | 0.026 | 0.7-1.73 mmol/L0.88-2.28 mmol/L | SST |
Helicobacter pylori antibody | Serum | Negative | | | SST |
Hematocrit (Hct) | Whole blood | Male: 39-49% Female: 35-45% (age-dependent) | 0.01 | Male: 0.39-0.49 Female: 0.35-0.45 | Lavender |
Hemoglobin A1c (See Glycated Hemoglobin) | Serum | | | | |
Hemoglobin A2 (HbA2) | Whole blood | 1.5-3.5% of total hemoglobin | 0.01 | 0.015-0.035 | Lavender |
Hemoglobin electrophoresis | Whole blood | HbA: > 95% HbA2: 1.5-3.5% | | | Lavender |
Hemoglobin, fetal (HbF) | Whole blood | Adult: < 2% (varies with age) | | | Lavender |
Hemoglobin, total (Hb) | Whole blood | Male: 13.6-17.5 g/dL Female: 12.0-15.5 g/dL Panic: 7 g/dL (age-dependent) | 10.00 | Male: 136-175 g/L Female: 120-155 g/L | Lavender |
Hemosiderin | Urine | Negative | | | Urine container |
HIV viral load | Plasma | Negative | | | Lavender |
Homocysteine | Plasma | 4-12 mcmol/L | 1.00 | 4-12 mcmol/L | Lavender |
5-Hydroxyindoleacetic acid (5-HIAA) | Urine | 2-8 mg/24 h | 5.23 | 10-40 mcmol/d | Urine bottle containing hydrochloric acid |
IgG index | Serum and CSF | 0.29-0.59 ratio | | | SST and plastic tube for CSF |
Immunoglobulins (Ig) | Serum | IgA: 78-367 mg/dL IgG: 583-1761 mg/dL IgM: 52-335 mg/dL | 0.01 | IgA: 0.78-3.67 g/L IgG: 5.83-17.6 g/L IgM: 0.52-3.35 g/L | SST |
Insulin, immunoreactive | Serum | 6-35 mcU/mL | 7.18 | 42-243 pmol/L | SST |
Insulin-like growth factor-1 | Plasma | 123-463 ng/mL (age- and sex-dependent) | 1.0 | 123-463 mcg/L | SST |
Iron (Fe2+) | Serum | 50-175 mcg/dL | 0.18 | 9-31 mcmol/L | SST |
Iron-binding capacity, total (TIBC) | Serum | 250-460 mcg/dL | 0.18 | 45-82 mcmol/L | SST |
Lactate dehydrogenase (LDH) | Serum | 88-230 units/L (laboratory-specific) | 0.02 | 1.46-3.82 mckat/L (laboratory-specific) | SST |
Lactic acid (lactate) | Venous blood | 0.5-2.0 mEq/L | 1.00 | 0.5-2.0 mmol/L | Gray |
LDL cholesterol | Serum | < 130 mg/dL | 0.026 | < 3.37 mmol/L | SST |
Lead (Pb) | Whole blood | Child: < 25 mcg/dL Adult: < 40 mcg/dL | 0.05 | Child: < 1.21 mcmol/L Adult: < 1.93 mcmol/L | Navy |
Lecithin/sphingomyelin (L/S) ratio | Amniotic fluid | > 2.0 (method-dependent) | | | Collect in a plastic tube |
Leukocyte alkaline phosphatase (LAP) | Whole blood | 40-130Based on 0 to 4+ rating of 100 polymorphonuclear neutrophils stained for alkaline phosphatase | | | Green |
Leukocyte (white blood cell) count, total (WBC count) | Whole blood | 4.8-10.8 103/mcL Panic: < 1.5 < 103/mcL | 1.00 | 4.8-10.8 109/L | Lavender |
Lipase | Serum | 0-160 units/L (laboratory-specific) | 0.02 | 0-2.66 mckat/L (laboratory-specific) | SST |
Luteinizing hormone (LH) | Serum | Female: | 1.00 | | SST |
Follicular phase 1-18 mU/mL | 1-18 units/L |
Luteal phase 0.4-20 mU/mL | 0.4-20 units/L |
Midcycle 24-105 mU/mL | 24-105 units/L |
Postmenopausal 15-62 mU/mL | 15-62 units/L |
Male: 1-10 mU/mL (laboratory-specific) | Male: 1-10 units/L (laboratory-specific) |
Lymphocyte count | Whole blood | 0.8-3.5 103/mcL | 1.00 | 0.8-3.5 109/L | Lavender |
Magnesium (Mg2+) | Serum | 1.8-3.0 mg/dL Panic: < 0.5 or > 4.5 mg/dL | 0.41 | 0.75-1.25 mmol/L | SST |
Mean corpuscular hemoglobin (MCH) | Whole blood | 26-34 pg | | | Lavender |
Mean corpuscular hemoglobin concentration (MCHC) | Whole blood | 31-36 g/dL | 10.00 | 310-360 g/L | Lavender |
Mean corpuscular volume (MCV) | Whole blood | 80-100 fL | | | Lavender |
Metanephrines | Urine | 0.3-0.9 mg/24 h | 5.46 | 1.6-4.9 mcmol/d | Urine bottle containing hydrochloric acid |
Methemoglobin (MetHb) | Whole blood | < 1% of total hemoglobin | 0.01 | < 0.01 fraction of total hemoglobin | Green |
Methylmalonic acid | Serum | 0-0.05 mg/L | 8.475 | 0-0.4 mcmol/L | SST |
Monocyte count | Whole blood | 0.2-0.8 103/mcL | 1.00 | 0.2-0.8 109/L | Lavender |
Neutrophil count | Whole blood | 2.2-8.6 103/mcL | 1.00 | 2.2-8.6 109/L | Lavender |
Osmolality | Serum | 275-293 mosm/kg H2O Panic: < 240 or > 320 mosm/kg H2O | 1.00 | 275-293 mmol/kg H2O | SST |
Urine | Random: 100-900 mosm/kg H2O | 1.00 | Random: 100-900 mmol/kg H2O | Urine container |
Oxygen, partial pressure (Po2) | Whole blood | 83-108 mm Hg | 0.13 | 11.04-14.36 kPa | Heparinized syringe (iced) |
Parathyroid hormone (PTH) | Serum | Intact PTH: 11-54 pg/mL (laboratory-specific) | 0.11 | Intact PTH: 1.2-5.7 pmol/L (laboratory-specific) | Red |
Partial thromboplastin time, activated (PTT) | Plasma | 25-35 seconds (range varies) panic: 60 seconds | | | Blue |
pH | Whole blood | Arterial: 7.35-7.45Venous: 7.31-7.41 | | | Heparinized syringe (iced) |
Phosphorus | Serum | 2.5-4.5 mg/dL panic: < 1.0 mg/dL | 0.32 | 0.8-1.45 mmol/L | SST |
Platelet count (Plt) | Whole blood | 150-450 103/mcL Panic: < 25 < 103/mcL | 1.0 | 150-450 109/L Panic: < 25 < 109/L | Lavender |
Platelet-associated IgG | Whole blood | Negative | | | Lavender |
Porphobilinogen (PBG) | Urine | Negative | | | Protect from light |
Potassium (K+) | Serum | 3.5-5.0 mEq/L panic: < 3.0 or > 6.0 mEq/L | 1.00 | 3.5-5.0 mmol/L | SST |
Prolactin (PRL) | Serum | < 20 ng/mL | 1.00 | < 20 mcg/L | SST |
Prostate-specific antigen (PSA) | Serum | 0-4 ng/mL | 1.00 | 0-4 mcg/L | SST |
Protein C | Plasma | 71-176% | | | Blue |
Protein electrophoresis | Serum | Adults: Albumin: 3.3-4.7 g/dL 1: 0.1-0.4 g/dL 2: 0.3-0.9 g/dL 2: 0.7-1.5 g/dL : 0.5-1.4 g/dL | 10.00 | 33-47 g/L1-4 g/L3-9 g/L7-15 g/L5-14 g/L | SST |
Protein S (antigen) | Plasma | 76-178% | | | Blue |
Protein, total | Serum | 6.0-8.0 g/dL | 10.00 | 60-80 g/L | SST |
Prothrombin time (PT) | Whole blood | 11-15 seconds panic: 30 seconds (laboratory-specific) | | | Blue |
Red blood cell count | Whole blood | 4.7-6.1 106/mcL | 1.00 | 4.7-6.1 1012/L | Lavender |
Red cell volume | Whole blood | 25-35 mL/kg | | | Green |
Renin activity (PRA) | Plasma | High-sodium diet (75-150 mEq Na+/d): Supine: 0.2-2.3 ng/mL/h Standing: 1.3-4.0 ng/mL/h) Low-sodium diet (30-75 mEq Na+/d): Standing: 4.0-7.7 ng/mL/h) | | | Lavender |
Reptilase clotting time | Plasma | 13-19 seconds | | | Blue |
Reticulocyte count | Whole blood | 33-137 103/mcL | 1.00 | 33-137 109/L | Lavender |
Russell's viper venom clotting time (dilute) (RVVT) | Plasma | 24-37 seconds | | | Blue |
Salicylate (aspirin, others) | Serum | 20-30 mg/dL panic: > 35 mg/dL | 10.00 | 200-300 mg/L | SST |
Sodium (Na+) | Serum | 135-145 mEq/L panic: < 125 or > 155 mEq/L | 1.00 | 135-145 mmol/L | SST |
Testosterone | Serum | Male: 175-781 ng/dL Female: 10-75 ng/dL | 0.0347 | Male: 6-27 nmol/L Female: 0.3-2.6 nmol/L | SST |
Thrombin time | Plasma | 8-12 seconds (laboratory-specific) | | | Blue |
Thyroglobulin | Serum | 3-42 ng/mL | 1.00 | 3-42 mcg/L | SST |
Thyroid-stimulating hormone (TSH) | Serum | 0.4-6 mcU/mL | 1.00 | 0.4-6 mU/L | SST |
Thyroid-stimulating hormone receptor antibody (TSH-R Ab [stim]) | Serum | < 130% of basal activity; based on cAMP generation in thyroid cell tissue culture | | | |
Thyroxine, free (FT4) | Serum | 9-24 pmol/L (varies with method) | | | SST |
Thyroxine (T4), total | Serum | 5-11 mcg/dL | 12.80 | 64-142 nmol/L | SST |
Thyroxine index, free (FT4I) | Serum | 6.5-12.5 | | | SST |
Transferrin | Serum | 190-375 mg/dL | 0.01 | 1.9-3.75 g/L | SST |
Triglycerides | Serum | < 165 mg/dL | 0.01 | < 1.8 mmol/L | SST (fasting) |
Triiodothyronine (T3), total | Serum | 95-190 ng/dL | 0.015 | 1.5-2.9 nmol/L | SST |
Troponin-I (cTnI) | Serum | < 0.05 ng/mL | | | SST |
Uric acid | Serum | Male: 2.4-7.4 mg/dL Female: 1.4-5.8 mg/dL | 59.48 | Male: 140-440 mcmol/L Female: 80-350 mcmol/L | SST |
Vanillylmandelic acid (VMA) | Urine | 2-7 mg/24 h | 5.05 | 10-35 mcmol/d | Urine bottle containing hydrochloric acid |
Vitamin B12 | Serum | 140-820 pg/mL | 0.74 | 100-600 pmol/L | SST |
Vitamin B12 absorption test (Schilling test) | 24-hour urine | Excretion of > 8% of administered dose | | | Urine bottle |
Vitamin D, 25-hydroxy (25[OH]D) | Serum | 10-50 ng/mL | 2.5 | 25-125 nmol/L | SST |
Vitamin D, 1,25-dihydroxy (1,25[OH]2D) | Serum | 20-76 pg/mL | 2.4 | 48-182 pmol/L | SST |
White blood cell count | Whole blood | 4.8-10.8 103/mcL | 1.00 | 4.8-10.8 109/L | Lavender |
1The reference ranges given here in conventional units and in SI units are from several large medical centers. Always use the reference ranges provided by your clinical laboratory, since ranges may be method-dependent. |
2Reference: Young DS: Implementation of SI units for clinical laboratory data. Ann Intern Med 1987;106:114; JAMA Instructions for Authors, JAMA 1997;278:74. |