ng/mL to nmol/L Calculator

A US report says ng/mL, while a UK or Canada report says nmol/L. Pick your substance to switch.

The ng/mL to nmol/L formula

Mass concentration becomes molar concentration when you divide by the molar mass (Wikipedia: Molar concentration).

One ng/mL is 1,000 ng per liter, so divide 1,000 by the molar mass to get nmol/L for each ng/mL.

Take 30 ng/mL of Vitamin D (25-OH D3). 30 × 1,000 ÷ 400.64 gives 74.88 nmol/L.

Take 30 ng/mL of Testosterone. 30 × 1,000 ÷ 288.42 gives 104.01 nmol/L.

ng/mL to nmol/L by substance

Value in ng/mL.

Substance. It sets the molar mass.

nmol/L is the result. The last column gives the factor for 1 ng/mL.

How to convert ng/mL to nmol/L step by step

1. Enter the value in ng/mL.
2. Pick the substance, or enter its molar mass.
3. Read the result in nmol/L.
4. Check it against the quick table.

For vitamin D, 1 ng/mL is about 2.5 nmol/L with the molar mass of 25-OH D3 used here. This page checks maths only. It is not medical advice, so ask your lab or clinician about any result or dose.

ng/mL to nmol/L conversion table

The highlighted row is the default of the calculator. The last column gives nmol/L per 1 ng/mL.

A quick mental shortcut for ng/mL to nmol/L

Divide 1,000 by the molar mass for the factor.

For vitamin D the factor is about 2.5.

What ng/mL measures

ng/mL means nanograms of a substance in one milliliter of blood or serum.

US reports use it for vitamin D and many hormones.

What nmol/L measures

nmol/L means billionths of a mole in one liter of fluid (Wikipedia: Molar concentration).

Many labs outside the US use it.

Why the substance matters

A mole is a count of particles, and heavier particles weigh more for the same count (Wikipedia: Molar mass).

So the same ng/mL gives a different nmol/L for each substance.

Example: Vitamin D (25-OH D3)

For Vitamin D (25-OH D3), the molar mass used is 400.64 g per mol.

So 30 ng/mL is 74.88 nmol/L.

Example: Testosterone

For Testosterone, the molar mass used is 288.42 g per mol.

So 30 ng/mL is 104.01 nmol/L.

Example: Iron

For Iron, the molar mass used is 55.85 g per mol.

So 30 ng/mL is 537.15 nmol/L.

Your own substance

If your substance is not in the list, enter its own molar mass.

Find it on the product label or in a trusted reference table.

Going the other way

To go back, multiply the nmol/L by the molar mass and divide by 1,000.

For Vitamin D (25-OH D3), 74.88 nmol/L goes back to 30 ng/mL.

Check your answer

Reverse the answer with the back formula.

For Vitamin D (25-OH D3), 74.88 nmol/L should return 30 ng/mL.

Quick conversion answers

Where this conversion is used

Vitamin and hormone tests are often reported in ng/mL.

Many labs outside the US report hormones and vitamins in nmol/L.

Common mistakes to avoid

• Using the wrong substance. Each substance has its own molar mass.
• Mixing up the direction. Here 50 ng/mL of Testosterone is 173.36 nmol/L, so a correct answer comes out bigger than the number you start with.
• Mixing dL, L and mL. A liter is 10 deciliters and 1,000 mL.
• Rounding too early. The answer for 50 ng/mL of Testosterone is 173.36 nmol/L. Cut it to 170 nmol/L and you are off by about 1.9 percent, and the gap grows if you reuse it.

Related converters

• ng/mL to nM
• ng/dL to nmol/L
• nmol/L to ng/dL
• µg/dL to mmol/L
• nmol/L to ng/mL converter
• ng/mL to ppm converter

Example: Glucose

For Glucose, the molar mass used is 180.16 g per mol.

So 20 ng/mL is 111.01 nmol/L.

Example: Cholesterol

For Cholesterol, the molar mass used is 386.65 g per mol.

So 50 ng/mL is 129.32 nmol/L.

Frequently asked questions

Sources

• Wikipedia: Molar concentration (en.wikipedia.org)
• Wikipedia: Mass concentration (chemistry) (en.wikipedia.org)
• Wikipedia: Molar mass (en.wikipedia.org)