BUN / Urea: mg/dL (BUN) to mmol/L (urea)
Convert BUN / Urea between mg/dL (BUN) and mmol/L (urea) — The US reports blood urea nitrogen (BUN) in mg/dL, while most countries report urea in mmol/L. Type in either box to convert both ways.
BUN / Urea conversion table (mg/dL (BUN) to mmol/L (urea))
| BUN / Urea (mg/dL (BUN)) | BUN / Urea (mmol/L (urea)) |
|---|---|
| 5 mg/dL (BUN) | 1.78486 mmol/L (urea) |
| 7 mg/dL (BUN) | 2.4988 mmol/L (urea) |
| 10 mg/dL (BUN) | 3.56972 mmol/L (urea) |
| 15 mg/dL (BUN) | 5.35458 mmol/L (urea) |
| 20 mg/dL (BUN) | 7.13944 mmol/L (urea) |
| 25 mg/dL (BUN) | 8.9243 mmol/L (urea) |
| 40 mg/dL (BUN) | 14.2789 mmol/L (urea) |
How to convert BUN / Urea from mg/dL (BUN) to mmol/L (urea)
To convert BUN / Urea, multiply BUN in mg/dL by 0.357 — BUN measures nitrogen (2 atoms per urea molecule), so this converts blood urea nitrogen to urea in mmol/L. For example, 1 mg/dL (BUN) equals 0.356972 mmol/L (urea). The converter above runs the exact factor at full precision and updates as you type; the swap button flips the direction.
Frequently asked questions
How do you convert BUN / Urea from mg/dL (BUN) to mmol/L (urea)?
Multiply BUN in mg/dL by 0.357 — BUN measures nitrogen (2 atoms per urea molecule), so this converts blood urea nitrogen to urea in mmol/L. For example, 1 mg/dL (BUN) is 0.356972 mmol/L (urea). The converter above does this instantly and works both ways — type a value in either box. It uses the exact factor at full precision, so the result matches published clinical conversions.
What is a normal BUN / Urea level?
Typical BUN is about 7–20 mg/dL, roughly 2.5–7.1 mmol/L of urea; it varies with hydration, diet and kidney function. These are general adult figures only — the reference interval on your own lab report is what applies to you, and it can differ by lab, method, age and sex. The conversion table above runs from 5 to 40 mg/dL (BUN), or 1.78486 to 14.2789 mmol/L (urea), so a range quoted in either system can be lined up against your own figure.
Why is BUN / Urea reported in different units?
The US reports blood urea nitrogen (BUN) in mg/dL, while most countries report urea in mmol/L. The two systems describe the same measurement, so a value converts exactly from one to the other with no loss of meaning — only the units and the number change. That is why guidelines, journals and lab reports from different countries quote different numbers for the same BUN / Urea result. The two boxes above are labelled mg/dL (BUN) and mmol/L (urea), so you can read a value in whichever system your own report uses.
Is this BUN / Urea converter accurate and free?
Yes — this BUN / Urea converter is both accurate and free. It applies the standard, published conversion factor at full double precision in your browser, with nothing uploaded or stored, and there is no sign-up or usage limit. It converts units only and does not interpret or diagnose results.
This is a unit-conversion reference tool, not a diagnosis or medical advice. Reference intervals are general adult guides that vary by laboratory, method and individual — always read your result against the range printed on your own report and discuss it with a qualified healthcare professional.
More lab converters
GlucoseHbA1cCholesterolTriglyceridesCreatinineVitamin D All lab converters →