Sodium: normal range and what it means
Short answer: The normal sodium range is 135 – 145 mmol/L for adults. Labs differ a little, so also check the range printed on your report.
Check your value
Where does your sodium sit?
Same number as mEq/L.
Your result
Type the number from your lab report to see where it sits.
Calculators that use your sodium
Upload your whole lab report and see every marker, with this value already in. Free, no account.
Add the rest of your reportWorked out in your browser. Nothing you type is sent or saved.
Information, not a diagnosis. Talk to a doctor about your result, and sooner if you feel unwell.
A tightly controlled electrolyte for fluid balance.
Normal range
Adult reference range.
- Low< 135 mmol/L
- Normal135 – 145 mmol/L
- High≥ 145 mmol/L
What it measures
The main electrolyte outside your cells, and the one that sets your body’s water balance. It is held in a very tight range, so even small deviations are meaningful.
What moves it
Water balance far more than salt intake. It reflects how dilute or concentrated your blood is, so fluid intake, sweating and some medications move it.
How to bring it into range
Abnormal results are usually about water rather than salt intake, and are a medical question rather than a dietary one.
How fast it responds
Hours to days.
Also reported as: na · serum sodium
See where your own value lands
Upload a lab report and HealthOS reads all 88 markers, personalises every range to your sex and age, and tells you which ones actually need attention. Free, no account needed.
Check my blood testGet this marker explained for your own numbers
We’ll send you a short guide to reading this marker in context — what to check alongside it, and when a value is worth acting on.
One email about this marker. No spam, unsubscribe anytime.
We handle your details as described in our Privacy Policy.
Common questions
- What is the normal sodium range?
- The normal sodium range is 135 – 145 mmol/L for adults. Labs differ a little, so also check the range printed on your report.
- What does a high Sodium mean?
- A value above the reference band means Sodium is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my Sodium?
- Abnormal results are usually about water rather than salt intake, and are a medical question rather than a dietary one.
Related markers
More in Kidney
Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.