Phosphorus unit converter
Convert phosphorus between mg/dL and mmol/L. Type in either box. The factors come from our catalog and are checked by code.
AI-verified against cited sources. Awaiting expert reviewLast reviewed 2026-10-03
1 mg/dL = 0.3229 mmol/L. Nothing you type here leaves your browser.
The conversion
- 1 mg/dL = 0.3229 mmol/LFrom mg/dL to mmol/L: divide by 3.097. Back again: multiply by 3.097.
Mass and molar units are linked by the molecular weight: 30.974 g/mol (elemental phosphorus (P), standard atomic weight. Results in mg/dL are the mass of phosphorus, not of the phosphate ion.). Source: National Library of Medicine, PubChem.
Common values
From zero to about twice the usual upper limit, plus the usual limits themselves.
| mg/dL | mmol/L |
|---|---|
| 1 | 0.32 |
| 2 | 0.65 |
| 2.5 | 0.81 |
| 3 | 0.97 |
| 4 | 1.29 |
| 4.5 | 1.45 |
| 5 | 1.61 |
| 6 | 1.94 |
| 7 | 2.26 |
| 8 | 2.58 |
| 9 | 2.91 |
Usual ranges in each unit
What labs print as the reference range, by who was tested. Sources for each range are on the Phosphorus page.
| Who | mg/dL | mmol/L |
|---|---|---|
| 18+ | 2.5–4.5 | 0.81–1.45 |
| 16–17 | 3.1–4.7 | 1–1.52 |
| Men, 14–15 | 3.5–5.3 | 1.13–1.71 |
| Women, 14–15 | 3.5–4.9 | 1.13–1.58 |
| Men, 5–13 | 3.7–5.4 | 1.19–1.74 |
| Women, 8–13 | 4–5.2 | 1.29–1.68 |
| Men, 1–4 | 4.3–5.4 | 1.39–1.74 |
| Women, 1–7 | 4.3–5.4 | 1.39–1.74 |