Sodium-Potassium Ratio Calculator

The Sodium-Potassium Ratio is a key indicator of cardiovascular health and electrolyte balance. It is calculated by dividing your daily sodium intake by your daily potassium intake.

Formula: Mass ratio = Sodium (mg) / Potassium (mg)

Why It Matters: Sodium and potassium work together to regulate fluid balance, nerve signals, and muscle contractions. When sodium is too high relative to potassium, blood pressure rises and cardiovascular risk increases.

Two different ratios go by the same name, and mixing them up is a 1.7x error

This trips up almost every page on the subject, and it is worth getting straight before you read any target number.

A mass ratio divides milligrams by milligrams. That is what this calculator shows, because milligrams are what food labels give you.

A molar ratio divides moles by moles, counting atoms rather than weight. Sodium weighs 22.99 g/mol and potassium 39.10 g/mol, so a potassium atom is about 1.70 times heavier. Converting between them:

Molar ratio = Mass ratio × 39.10 ÷ 22.99 = Mass ratio × 1.70

The WHO recommends a molar ratio of 1.0, which is where the famous “keep it under 1” comes from. In the milligram terms you actually measure, that same target is a mass ratio of 0.59, not 1.0. A page that tells you to keep the mg/mg figure under 1.0 is quoting a target that is 70% too loose.

You can check this against WHO’s own two intake targets: under 2,000 mg sodium and at least 3,510 mg potassium. That is a mass ratio of 2000 ÷ 3510 = 0.57, and a molar ratio of 0.97. The two recommendations were designed to land on a molar 1.0 together.

Optimal Ranges (mass ratio, mg per mg):

• Below 0.6: Excellent. This is the WHO target expressed in milligrams.
• 0.6 – 1.0: Good. Better than most people manage, though above the WHO figure.
• 1.0 – 2.0: Elevated. Consider increasing potassium-rich foods or reducing sodium.
• Above 2.0: High risk. Associated with significantly increased risk of heart disease and stroke.

For reference, the average American lands near 1.4 in mass terms, which is well inside the elevated band.

Recommended Daily Intakes:

• Sodium: Less than 2,300 mg (ideally under 1,500 mg per the American Heart Association)
• Potassium: At least 2,600 mg for women, 3,400 mg for men (US Adequate Intake)

Potassium-Rich Foods:

Practical Example: If you consume 2,400 mg of sodium and 3,000 mg of potassium daily, your mass ratio is 2400 / 3000 = 0.80, which falls in the good band. The molar equivalent is 0.80 × 1.70 = 1.36, so by the WHO’s own measure you are still above target. Both numbers describe the same diet.

Tips:

• The World Health Organization target is a molar ratio below 1.0, which is a mass ratio below 0.59.
• Most people consume too much sodium and not enough potassium. Raising potassium is usually the easier half.
• Processed foods are the main source of excess sodium, not the salt shaker.
• Fresh fruits, vegetables, and legumes are the best sources of potassium.
• Tracking both minerals together gives a more complete picture than tracking either one alone. Two people eating the same amount of salt can sit in very different bands.

One caveat on the potassium side: if you have chronic kidney disease or take a potassium-sparing diuretic, an ACE inhibitor, or an ARB, do not chase a high potassium intake on the strength of a web calculator. Impaired kidneys clear potassium poorly, and hyperkalemia is dangerous. That conversation belongs with your doctor.