| Marker | US | SI | Factor | |
|---|---|---|---|---|
| Total Testosterone | ng/dL | ⇆ | nmol/L | ×0.0347 — from 288.42 g/mol, testosterone |
| Free Testosterone | ng/dL | ⇆ | pmol/L | ×34.7 — from 288.42 g/mol, testosterone |
| Estradiol | pg/mL | ⇆ | pmol/L | ×3.671 — from 272.38 g/mol, 17β-estradiol |
| Glucose | mg/dL | ⇆ | mmol/L | ×0.0555 — from 180.16 g/mol, D-glucose |
| Total / LDL / HDL Cholesterol | mg/dL | ⇆ | mmol/L | ×0.0259 — from 386.65 g/mol, cholesterol |
| Triglycerides | mg/dL | ⇆ | mmol/L | ×0.0113 — from 885.4 g/mol, triolein (the convention) |
| Creatinine | mg/dL | ⇆ | µmol/L | ×88.4 — from 113.12 g/mol, creatinine |
| Vitamin D (25-OH) | ng/mL | ⇆ | nmol/L | ×2.496 — from 400.64 g/mol, 25-hydroxyvitamin D₃ |
| Vitamin B12 | pg/mL | ⇆ | pmol/L | ×0.738 — from 1355.4 g/mol, cyanocobalamin |
| Ferritin | ng/mL | ⇆ | µg/L | ng/mL and µg/L are the same unit written twice |
| Cortisol | µg/dL | ⇆ | nmol/L | ×27.59 — from 362.46 g/mol, cortisol |
| DHEA-S | µg/dL | ⇆ | µmol/L | ×0.02714 — from 368.49 g/mol, DHEA sulfate |
| Insulin | µIU/mL | ⇆ | pmol/L | 1 µIU/mL = 6.945 pmol/L on the 24.8 IU/mg insulin standard. Some labs use 6.00, from the 28.8 IU/mg standard — a 14% difference, so never mix the two |
| IGF-1 | ng/mL | ⇆ | nmol/L | ×0.1307 — from 7649.0 g/mol, IGF-1 |
| Uric Acid | mg/dL | ⇆ | µmol/L | ×59.48 — from 168.11 g/mol, uric acid |
| Calcium | mg/dL | ⇆ | mmol/L | ×0.2495 — from 40.08 g/mol, calcium |
| Lp(a) | mg/dL | ⇆ | nmol/L | mass-to-particle conversion depends on apo(a) isoform size — approximate by nature, which is why guidelines ask for nmol/L directly |
The four that cause real misreadings
Testosterone
A US lab reports ng/dL, most of the rest of the world nmol/L. 600 ng/dL and 20.8 nmol/L are the same blood. Reading a nmol/L result against a ng/dL range is how a perfectly normal man concludes he is at rock bottom.
Vitamin D
ng/mL against nmol/L is a 2.5× difference. A result of 30 is deficient in ng/mL and frankly low in nmol/L — 30 nmol/L is 12 ng/mL.
Glucose
mg/dL and mmol/L differ by 18×. 5.5 mmol/L is 99 mg/dL, which is normal; read as mg/dL it looks like a number that cannot be real.
Vitamin B12
pg/mL against pmol/L. 500 pg/mL is 369 pmol/L — the same result, and only one of them looks reassuring against a range that starts at 200.
Converting is not the same as comparing. Two labs can report the same unit and still disagree, because they ran different assays — sensitive estradiol and standard estradiol are not interchangeable in men, and a calculated free testosterone does not match one measured by equilibrium dialysis. The clean way to track anything over time is the same lab, the same assay, the same time of day.
This tool does not diagnose anything. It puts a number next to a published interval and shows the arithmetic that got there. It cannot see your symptoms, your medications, your history or the assay your lab ran. A result outside the outer bounds belongs in front of a clinician, not in a supplement search.
Where to go with this
Read a converted resultNow that the number is in the right unit, see where it sits against the range and what could have moved it.Every marker A to Z103 markers with the normal range, the optimal range and what moves each one.Panels you can orderWhat each panel actually settles, and what it costs with the code.