How do I convert Sodium from mmol/L to mg/dL?

mg/dL = mmol/L × 2.299. For example, 140 mmol/L equals 322 mg/dL.

How many mg/dL are 140 mmol/L?

140 mmol/L equal 322 mg/dL (Sodium).

Electrolytes & minerals

mg/dL = mmol/L × 2.299

Enter a value in any unit and all other units fill in.

mmol/L = mEq/L mg/dL

mmol/L → mg/dL	mg/dL = mmol/L × 2.299
mg/dL → mmol/L	mmol/L = mg/dL × 0.4349

Highlighted: values inside the adult reference range.

135 – 145 mmol/L = 310.4 – 333.4 mg/dL

Source: MedlinePlus (NLM): Sodium blood test · Last reviewed: 2026-10-14