Blood Sugar Converter: mmol/L to mg/dL and Back

Use this mmol/L to mg/dL converter in either direction: type a value in either field and the other updates instantly. mg/dL and mmol/L describe the same glucose level in different units: 1 mmol/L equals about 18 mg/dL. To convert mmol/L to mg/dL, multiply by 18 (5.5 mmol/L is about 99 mg/dL); to go the other way, divide by 18. It is built for CGM users, the caregivers following their readings, and anyone comparing a meter, an app and a lab report from different countries.

mmol/L vs mg/dL: how the conversion works

mg/dL (milligrams per decilitre) measures the weight of glucose in a volume of blood, while mmol/L (millimoles per litre) counts glucose molecules. Because glucose has a molar mass of about 180.16 g/mol, one mmol/L equals 18.016 mg/dL. In practice everyone rounds to 18:

• mmol/L to mg/dL: multiply by 18 (5.5 mmol/L is about 99 mg/dL)
• mg/dL to mmol/L: divide by 18 (100 mg/dL is about 5.6 mmol/L)

Each substance measured in blood has its own factor, so this page is for glucose only: cholesterol, triglycerides and creatinine convert with different numbers, and using 18 on them gives nonsense.

Where each unit is used

The United States reports glucose in mg/dL, and so do Japan, India, much of Latin America and several European countries such as France, Italy and Spain. The United Kingdom, Ireland, Canada, Australia, New Zealand, China, South Africa, the Netherlands, Switzerland and the Nordic countries report mmol/L, the SI unit, and Germany uses both, region by region. Most countries moved their laboratory reporting to SI units decades ago while the US kept the older mass-based unit, which is why a meter bought abroad, a CGM app set up for another country and a lab report can show the same glucose in different ways. Both numbers describe exactly the same level; only the unit differs, which is why a blood sugar converter is the quickest way to compare them.

Quick answers: common mmol/L and mg/dL values

Reading a UK or Canadian number and want the US one? 4.0 mmol/L is about 72 mg/dL; 5.0 mmol/L is about 90 mg/dL; 5.2 mmol/L is about 94 mg/dL; 5.3 mmol/L is about 95 mg/dL; 5.5 mmol/L is about 99 mg/dL; 5.7 mmol/L is about 103 mg/dL; 6.0 mmol/L is about 108 mg/dL; 6.1 mmol/L is about 110 mg/dL; 6.2 mmol/L is about 112 mg/dL; 7.0 mmol/L is about 126 mg/dL; 8.0 mmol/L is about 144 mg/dL; 10.0 mmol/L is about 180 mg/dL. 7.8 mmol/L is about 140 mg/dL (140.5 exactly, which the converter rounds to 141).

Going the other way: 70 mg/dL is about 3.9 mmol/L; 80 mg/dL is about 4.4 mmol/L; 90 mg/dL is about 5.0 mmol/L; 100 mg/dL is about 5.6 mmol/L; 110 mg/dL is about 6.1 mmol/L; 120 mg/dL is about 6.7 mmol/L; 126 mg/dL is about 7.0 mmol/L; 140 mg/dL is about 7.8 mmol/L; 150 mg/dL is about 8.3 mmol/L; 160 mg/dL is about 8.9 mmol/L; 180 mg/dL is about 10.0 mmol/L; 200 mg/dL is about 11.1 mmol/L; 250 mg/dL is about 13.9 mmol/L; 300 mg/dL is about 16.7 mmol/L.

Blood sugar conversion chart

Common values side by side. The 70 to 180 mg/dL band (3.9 to 10.0 mmol/L) is the standard CGM target range used for time in range.

Prefer paper? Download the printable chart (PDF) and stick it on the fridge or in a school bag.

Need a value the chart above skips? The two tables below run the whole everyday range in both directions, computed with the exact 18.016 factor and rounded the way the converter rounds.

mmol/L to mg/dL table

mg/dL to mmol/L table

These bands follow the international consensus targets for CGM users. New to sensors? Start with our plain-English CGM guide, or check how much of your day sits inside the band with the Time in Range calculator.

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Frequently asked questions

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

Multiply the mmol/L value by 18. For example, 5.5 mmol/L is about 99 mg/dL. The precise factor is 18.016, because glucose has a molar mass of about 180.16 g/mol, but 18 is accurate enough for everyday use. The formula is for glucose only; cholesterol and triglycerides use different factors.

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

Divide the mg/dL value by 18 (or multiply by 0.0555). For example, 100 mg/dL is about 5.6 mmol/L.

What is 7.0 mmol/L in mg/dL?

About 126 mg/dL (7.0 × 18.016 = 126.1). It is also the fasting cut-off the ADA uses for a diabetes diagnosis, 126 mg/dL, which is why this pair comes up so often.

What is 5.3 mmol in mg/dL?

About 95 mg/dL (5.3 × 18.016 = 95.5). As a fasting value it sits inside the normal band, which runs up to 5.6 mmol/L (100 mg/dL).

Which countries use mg/dL and which use mmol/L?

The United States, Japan, India, much of Latin America and several European countries (France, Italy, Spain among them) report blood glucose in mg/dL. The United Kingdom, Ireland, Canada, Australia, New Zealand, China, South Africa, the Netherlands, Switzerland and the Nordic countries use mmol/L, and Germany uses both depending on the region. Both describe exactly the same glucose level, only the unit differs, which is why meters, CGM apps and lab reports can look so different between countries.

Why do the US and the UK use different blood sugar units?

Most countries switched laboratory reporting to SI units decades ago, and mmol/L, which counts glucose molecules, is the SI unit. The US kept the older mass-based mg/dL, and so did Japan, India and part of Europe. Meters and CGM apps follow the market they are sold in, so a device shows the unit of the country it was set up for; the number underneath is the same glucose.

What is a normal blood sugar level in both units?

For people without diabetes, fasting glucose is typically about 70 to 99 mg/dL (3.9 to 5.5 mmol/L). The ADA cut-offs for a fasting test are below 100 mg/dL (5.6 mmol/L) normal, 100 to 125 mg/dL (5.6 to 6.9 mmol/L) prediabetes and 126 mg/dL (7.0 mmol/L) or higher diabetes, confirmed by a repeat test. For people with diabetes who use a CGM, the international consensus uses 70 to 180 mg/dL (3.9 to 10.0 mmol/L) as the standard target range for time in range. Targets are individual, so always follow the range agreed with your care team.

Can Sugar Sense show both units?

Yes. Sugar Sense lets you switch between mg/dL and mmol/L at any time, and the change applies everywhere at once: the app on iPhone and Android, the Apple Watch and Wear OS, widgets and the Live Activity.

More free tools

• A1C Calculator: Convert A1C to Average Glucose
• Time in Range Calculator

This tool is for education only. It is not medical advice, it does not replace laboratory testing, and it must never be used for insulin dosing or other treatment decisions. Always work with your healthcare team. See our full medical disclaimer.