Urine Albumin Unit Converter
Urine Albumin Unit Converter
Convert urine albumin between mg/L, mg/dL and µg/mL — the first step before an albumin-to-creatinine ratio, which is the number that actually carries meaning.
Urine Albumin converter
Mass unitsUrine albumin 18 mg/L
Formula and conversion factors
µg/mL = mg/L (numerically identical)
ACR (mg/mmol) = albumin (mg/L) ÷ creatinine (mmol/L)
- mg/L ⇄ µg/mL
- the same quantity written two ways — 1 mg/L is 1 µg/mL, no factor is needed
- ACR
- albumin-to-creatinine ratio, reported in mg/mmol in the UK and mg/g in the US; 1 mg/mmol ≈ 8.84 mg/g
- albumin ≠ protein
- urine albumin is one component of total urine protein; the two are not interchangeable and are categorised on different thresholds
Worked example
Urine albumin 18 mg/L
18 ÷ 10 = 1.80 mg/dL
18 mg/L = 18.0 µg/mL
Inside the concentration guide, so the number looks reassuring on its own
But on a dilute sample with a urine creatinine of 3 mmol/L, ACR = 18 ÷ 3 = 6 mg/mmol → KDIGO A2, moderately increased
KDIGO albuminuria categories (albumin-to-creatinine ratio)
| Category | ACR (mg/mmol) | ACR (mg/g) | Term |
|---|---|---|---|
| A1 | < 3 | < 30 | Normal to mildly increased |
| A2 | 3 – 30 | 30 – 300 | Moderately increased |
| A3 | > 30 | > 300 | Severely increased |
Concentration units
| mg/L | mg/dL | µg/mL |
|---|---|---|
| 18 | 1.80 | 18.0 |
| 45 | 4.50 | 45.0 |
| 200 | 20.00 | 200.0 |
Why concentration alone is not enough
A urine albumin concentration on its own says very little, because it depends almost as much on how dilute the urine is as on how much albumin the kidney is leaking. Take the 18 mg/L loaded above. It sits inside any reasonable concentration guide and looks reassuring, but if that sample was dilute — a urine creatinine of 3 mmol/L, say — the albumin-to-creatinine ratio is 6 mg/mmol, which is KDIGO category A2, moderately increased. The concentration looked normal and the ratio was not. That is why the ratio is the number that carries meaning, and why the main reason to be careful with these units is to get the arithmetic right before that calculation.
The units themselves are simple. Milligrams per litre and micrograms per millilitre are numerically identical, so no factor is needed between them, and mg/dL is simply mg/L divided by ten. The ratio is then reported in mg/mmol in the UK and much of Europe and in mg/g in the United States, which is where most of the confusion in practice actually arises.
The vocabulary has moved on as well. Microalbuminuria and macroalbuminuria have been replaced by KDIGO’s A1, A2 and A3 categories, defined on the ratio: below 3 mg/mmol, 3 to 30, and above 30. It is also worth being clear that albumin is not the same as total urine protein, and that the reagent strip is insensitive to the concentrations that matter here — a negative dipstick does not exclude moderately increased albuminuria, which is precisely why a laboratory albumin measurement is requested.
Finally, a single raised result should be repeated before it is acted on. Exercise, fever, heart failure, poor glycaemic control, menstrual contamination and urinary tract infection all raise urine albumin transiently, and postural or orthostatic albuminuria is common in younger people. KDIGO asks for two or three abnormal samples over three months before albuminuria is treated as persistent, which avoids labelling people on the strength of one inconveniently timed specimen.
Frequently asked questions
How do I convert urine albumin from mg/L to mg/dL?
Divide by 10. A urine albumin of 18 mg/L is 1.80 mg/dL. Milligrams per litre and micrograms per millilitre are numerically identical, so no conversion is needed between those two.
Why is the albumin-to-creatinine ratio preferred over the concentration?
Because concentration reflects urine dilution as much as albumin leak. Dividing by the creatinine on the same sample corrects for that, which is why the ratio, not the concentration, defines the KDIGO albuminuria categories.
Are microalbuminuria and macroalbuminuria still used?
They have been replaced by KDIGO’s A1, A2 and A3 categories, based on the albumin-to-creatinine ratio. The older terms are discouraged because they wrongly suggest a different kind of albumin rather than a different amount.
Does a negative dipstick exclude albuminuria?
No. The reagent strip detects total protein and is insensitive at the concentrations that define category A2, so a negative dipstick does not exclude moderately increased albuminuria. A laboratory albumin measurement is needed.
What can raise urine albumin transiently?
Exercise, fever, heart failure, hyperglycaemia, menstrual contamination and urinary tract infection, as well as upright posture in younger people. Repeat an isolated raised result before acting on it.
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References
- KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int. 2024;105(4S).
- Miller WG, Bruns DE, Hortin GL, et al. Current issues in measurement and reporting of urinary albumin excretion. Clin Chem. 2009;55(1):24–38.