Biochemistry Urea Kidney Function

Urea Unit Converter

Convert total urea concentration between mmol/L, µmol/L, mg/dL, mg/L, µg/mL, and g/L.

Published on: 2026-08-29 · Last updated: 2026-08-29

Enter Urea Value

You can enter a value in any supported unit.

What does this converter do?

This urea unit converter changes total urea concentration between mmol/L, µmol/L, mg/dL, mg/100mL, mg%, mg/L, µg/mL, and g/L. It converts the complete urea molecule and must not be used to treat BUN as another urea unit.

Supported units

mmol/L · common SI reporting unit µmol/L · micromolar concentration mg/dL · total urea, not BUN mg/100mL · numerically equal to mg/dL mg% · historical notation equal to mg/dL mg/L · mass concentration per litre µg/mL · numerically equal to mg/L g/L · grams per litre

Conversion formulas

Urea mg/dL = mmol/L × 6.006
Urea mmol/L = mg/dL ÷ 6.006
Urea µmol/L = mmol/L × 1000
Urea mmol/L = µmol/L ÷ 1000
Urea mg/L = mmol/L × 60.06
Urea mmol/L = mg/L ÷ 60.06
Urea g/L = mmol/L × 0.06006
Urea mmol/L = g/L ÷ 0.06006
mg/100mL = mg/dL
mg% = mg/dL
µg/mL = mg/L

Example conversion

Example: a total urea result of 5 mmol/L is equivalent to approximately 30.03 mg/dL, 300.3 mg/L, 0.3003 g/L, and 5000 µmol/L.

Important laboratory note

This calculator converts total urea units only. Confirm that the original laboratory report says Urea rather than BUN or Urea Nitrogen. BUN requires a different conversion because it reports only the nitrogen contained in the urea molecule.

How to Convert Urea from mmol/L to mg/dL

To convert total urea from mmol/L to mg/dL, multiply the result by 6.006. The factor is based on the molecular mass of urea, approximately 60.06 g/mol.

For example, a urea concentration of 5 mmol/L multiplied by 6.006 equals approximately 30.03 mg/dL.

  • Urea mg/dL = Urea mmol/L × 6.006
  • 5 mmol/L = approximately 30.03 mg/dL
  • 7 mmol/L = approximately 42.04 mg/dL
  • 10 mmol/L = approximately 60.06 mg/dL

How to Convert Urea from mg/dL to mmol/L

To convert total urea from mg/dL to mmol/L, divide the mg/dL result by 6.006.

For example, a total urea result of 30 mg/dL divided by 6.006 equals approximately 5.00 mmol/L.

  • Urea mmol/L = Urea mg/dL ÷ 6.006
  • 20 mg/dL = approximately 3.33 mmol/L
  • 30 mg/dL = approximately 5.00 mmol/L
  • 40 mg/dL = approximately 6.66 mmol/L
  • 60 mg/dL = approximately 9.99 mmol/L

Equivalent Urea Reporting Units

Some urea reporting units use different names while representing the same numerical concentration. Recognizing these equivalents helps prevent unnecessary conversion errors.

  • mg/dL, mg/100mL, and mg% are numerically equivalent.
  • mg/L and µg/mL are numerically equivalent.
  • 1 mmol/L equals 1000 µmol/L.
  • 1 mg/dL equals 10 mg/L.
  • 1 g/L equals 1000 mg/L.
  • 1 mmol/L urea equals 6.006 mg/dL or 60.06 mg/L.

Urea and BUN Are Not the Same Reporting Format

Urea results report the concentration of the complete urea molecule. BUN, meaning blood urea nitrogen, reports only the nitrogen contained within urea.

A value reported as BUN mg/dL must not be entered as total urea mg/dL. Use the separate BUN to Urea Converter when converting between these two reporting systems.

  • Use the factor 6.006 only for total urea mmol/L and total urea mg/dL.
  • Do not use 6.006 to convert BUN mg/dL to urea mmol/L.
  • Check whether the laboratory report says Urea, BUN, or Urea Nitrogen before entering the value.

Common Urea Conversion Examples

The following examples show equivalent total urea concentrations. Values are rounded for practical display.

  • 2.5 mmol/L = approximately 15.02 mg/dL
  • 5 mmol/L = approximately 30.03 mg/dL
  • 7.5 mmol/L = approximately 45.05 mg/dL
  • 10 mmol/L = approximately 60.06 mg/dL
  • 30 mg/dL = approximately 5.00 mmol/L
  • 300 mg/L = approximately 5.00 mmol/L
  • 0.30 g/L = approximately 5.00 mmol/L

Clinical Context and Important Limitations

Urea is formed primarily in the liver during protein metabolism and is eliminated mainly through the kidneys. Its concentration may be influenced by renal function, hydration, protein intake, gastrointestinal bleeding, catabolic states, liver function, pregnancy, medications, and other clinical factors.

Converting a result does not change its clinical meaning. The converted value must be interpreted using an appropriate reference interval for the same analyte, specimen type, and reporting unit.

  • Use the analyte name and unit printed on the original laboratory report.
  • Do not apply serum reference intervals automatically to urine urea results.
  • Reference intervals vary by laboratory, specimen type, method, age, and clinical context.
  • This calculator does not diagnose kidney disease, dehydration, or liver disease.
  • Do not make treatment decisions from a converted value alone.

Frequently Asked Questions

How do I convert urea mmol/L to mg/dL? Multiply the mmol/L value by 6.006.

How do I convert urea mg/dL to mmol/L? Divide the mg/dL value by 6.006.

Is urea mg/L the same as µg/mL? Yes. The two units have the same numerical value.

Is urea mg/dL the same as BUN mg/dL? No. Total urea and BUN measure different mass components and require a separate conversion.

Can I use this converter for urine urea? The mathematical concentration conversion remains valid, but serum and urine results have different clinical uses and reference intervals.

References and Conversion Standards

  1. National Institute of Standards and Technology. Urea: molecular formula CH4N2O and molar mass 60.06 g/mol.
  2. UK Renal Registry. Appendix J: Laboratory Conversion Factors. Urea mg/dL = mmol/L × 6.0.
  3. Hosten AO. BUN and Creatinine. Clinical Methods. NCBI Bookshelf.