Blood test unit converter
Blood test results are reported in different units depending on where you had your test done. The same biomarker can appear as mg/dL in one country and mmol/L in another, making it difficult to compare results, look up reference ranges, or make sense of values you find in research or online resources.
This converter covers the most common blood markers and their unit conversions. Select the marker you are looking at, enter the value you have, and you will get the equivalent in the other unit alongside the typical reference range for that marker.
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Why units differ
Most countries use the International System of Units (SI), which expresses concentrations in millimoles per litre (mmol/L). The United States and a handful of other countries use conventional units, typically milligrams per decilitre (mg/dL). Neither is more accurate than the other — they are simply different ways of expressing the same measurement, and converting between them is always a fixed mathematical relationship specific to each molecule.
If you are tracking your health over time and have results from different sources, converting everything to one consistent unit makes it much easier to see how your values are moving. It also allows you to compare your results against research studies, which may report reference ranges in a unit different from the one on your lab report.
A note on reference ranges
The reference ranges shown here are general population averages. They tell you what most healthy people measure, not what is optimal for you specifically. A value within the reference range is not always a signal that everything is fine, and a value slightly outside it is not automatically cause for concern. For a deeper look at what reference ranges actually mean and where they come from, read our article on how reference ranges are calculated.