Who We Are
ConvertMedUnits.com is an independent educational resource that converts laboratory test values between the two measurement systems used around the world: SI units (mmol/L, µmol/L, nmol/L) used across most of the world, and conventional units (mg/dL, µg/dL, ng/mL) used mainly in the United States. Our content is produced and maintained by the ConvertMedUnits Editorial Team, who research each analyte, build each calculator, and cross-check every factor and reference range against published sources before it is published.
Our library spans more than 70 calculators across six areas — core conversions, hormones, metabolic markers, blood and heart tests, drugs and toxicology, and specialty and critical care — each covering a specific analyte and unit pair rather than a single generic converter.
We are not a substitute for a clinician or a laboratory. Everything here is educational information to help people understand and convert lab values — not medical advice, diagnosis, or treatment.
How We Derive Conversion Factors
Most lab conversions between mass units (like mg/dL) and molar units (like mmol/L) come directly from the substance's molecular weight. The molar concentration equals the mass concentration divided by the molecular weight, adjusted for the unit prefixes and the volume basis (per litre vs per decilitre). For example:
Glucose MW ≈ 180.16 g/mol → 1 mg/dL = (10 ÷ 180.16) mmol/L ≈ 0.0555 mmol/L (÷18) Because each factor depends on molecular weight, every analyte has its own number — glucose uses ~18, cholesterol ~38.67, and triglycerides ~88.57. We publish the factor and the underlying molecular weight on each page so the math is transparent and checkable. For enzyme activity, electrolytes (which use ion valence), and mass-to-mass conversions, we use the corresponding standard relationships rather than molecular weight, and we say so on the relevant pages.
Our Sources
We build and check our content against recognised references, including:
- Molecular weights and conversion factors from established clinical-chemistry references and the AMA Manual of Style SI conversion tables.
- Diabetes and glucose thresholds from the American Diabetes Association (fasting glucose, OGTT, HbA1c).
- Kidney function (eGFR) from the National Kidney Foundation and the race-free CKD-EPI 2021 equation (NIDDK).
- Uric acid and gout targets from the American College of Rheumatology.
- Laboratory unit references and typical intervals from published lab test directories such as Mayo Clinic Laboratories and ARUP Laboratories.
Each calculator page also lists the specific references we relied on in its "References" section.
About Reference Ranges
Reference ranges are not universal. They vary by laboratory, assay method, age, sex, pregnancy, and population, and guideline thresholds are updated over time. We present commonly cited ranges to give context, but we state clearly on every page that readers must compare their results against the reference interval printed on their own lab report and interpreted by their healthcare provider.
Review and Update Process
Before a page is published, the Editorial Team verifies the conversion factor against the analyte's molecular weight, recomputes the worked examples, and confirms reference ranges against current sources. Calculator logic is tested against known values. We revisit pages when guidelines change — for instance, adopting the race-free 2021 CKD-EPI equation for eGFR — and record when a page was last reviewed.
We welcome review and input from qualified healthcare and laboratory professionals. If you are a clinician, pharmacist, or medical laboratory scientist and would like to contribute to reviewing our content, please reach out via our contact page.
Accuracy and Corrections
We aim for every factor, range, and example to be correct, but errors are possible. If you spot something that looks wrong, please tell us through the contact page and we will review it promptly and correct it if needed. Accuracy matters more to us than being fast, and we would rather fix an issue than leave it.
Our Limitations
To be clear about what this site is and is not, we deliberately do not:
- provide diagnosis, treatment advice, or medication recommendations;
- interpret your individual results or tell you whether a value is "good" or "bad" for you personally;
- replace your laboratory's own reference ranges, which are the correct ones to compare against;
- claim that any reference range applies universally — ranges differ by lab, assay, age, sex, and population.
Our role is narrow and specific: to convert a value accurately between units and give you the context to understand it, so you can have a better conversation with the professional who ordered the test.
Advertising and Independence
This site may display advertising to support its running costs, as described in our privacy policy. Advertising never influences the conversion factors, reference ranges, or clinical context we publish. Our numbers come from the sources above, not from commercial considerations.
Medical Disclaimer
ConvertMedUnits provides educational information only. It is not medical advice and is not a substitute for professional diagnosis or treatment. Always seek the guidance of a qualified healthcare professional with any questions about a medical condition or lab result. See our full disclaimer for details.