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- Lab unit converter
- pg/mL to pmol/L
pg/mL to pmol/L
There is no single pg/mL to pmol/L factor. pg/mL counts the mass of a substance, pmol/L the number of its molecules, so the factor depends on the substance’s molar mass. Here are the 3 lab tests Soma converts in these units.
Tests and factors
| Test | Units | US → SI | SI → US | Molar mass |
|---|---|---|---|---|
| Vitamin B12 | pg/mL ⇄ pmol/L | × 0.73781 | × 1.3554 | 1355.37 g/mol |
| Free T3 | pg/mL ⇄ pmol/L | × 1.5362 | × 0.65097 | 650.97 g/mol |
| Estradiol | pg/mL ⇄ pmol/L | × 3.6713 | × 0.27238 | 272.38 g/mol |
The molar masses are the ones the Soma app converts with; each links to its compound on PubChem (U.S. National Library of Medicine). HbA1c uses the IFCC–NGSP master equation instead of a molar mass. Urea nitrogen counts the two nitrogen atoms of urea; phosphate is measured as phosphorus. Prolactin and insulin have no molar mass in these units: each uses the factor of the international standard its tests are calibrated to. ALT and AST count enzyme activity: 1 µkat/L is 60 U/L by definition. Mention of a source doesn’t mean it endorses Soma.
pmol/L = pg/mL ÷ 1.3554 · molar mass 1355.37 g/mol
Vitamin B12: formula and common values →This converter changes units only. It doesn’t tell you whether a number is in or out of any range: that depends on the range printed by your own lab, and on your doctor. Soma does not diagnose and is not medical advice.
Questions
Why is there no single pg/mL to pmol/L factor?
Going from mass to molecules needs the mass of one mole of the substance, and every substance has its own. So each test has its own factor: Vitamin B12: divide pg/mL by 1.3554; Free T3: multiply pg/mL by 1.5362; Estradiol: multiply pg/mL by 3.6713.
How do I convert pg/mL to pmol/L?
Find your test in the table and multiply by its factor; to go back, multiply by the other one. For example, 400 pg/mL of vitamin B12 is 295.1 pmol/L.
By unit pair
Soma converts straight from the PDF
Share a lab report to Soma, and it reads every row on your phone and converts the units for you, so a Quest result in mg/dL and a Synlab result in mmol/L sit on one chart, each against its own lab’s range. No account, nothing uploaded.