What is the exact conversion factor?

1 mmol/L of glucose equals 18.0182 mg/dL. It comes from the molar mass of glucose (180.156 g/mol) and the standard 1/10 ratio between mg/dL and mg/L.

Which countries use which unit?

The U.S., Japan, and some others use mg/dL. Most of Europe, the UK, Canada, Australia, and much of the rest of the world use mmol/L.

Why does the reference band depend on context?

A perfectly healthy person’s glucose rises after a meal. The ADA publishes separate cut-offs for fasting (≥ 8 h) and 2-hour post-meal readings; we don’t assign a band to random readings because the expected range is too wide.

Does a single reading mean I have diabetes?

No. The ADA requires repeat confirmatory testing — and clinicians look at HbA1c plus symptoms, not one finger-stick. Use the band as context, not a diagnosis.

Is my reading stored anywhere?

No. The converter runs entirely in your browser.

Blood Sugar Converter

Written by Golam Rabbani, Founder & Lead Engineer — Last updated 2026-05-01

This interactive tool requires JavaScript. Read the formula and worked example below; you can compute the result by hand.

How to use this blood sugar converter

Enter the blood glucose value and pick the unit (mg/dL or mmol/L) with the toggle.
Switching the unit converts your existing value automatically.
Select the reading context — fasting (≥ 8 h), post-meal (2 h after eating), or random / unspecified.
Press Convert to see the value in both units side by side, plus the ADA reference band where one applies.
Use Copy to save the converted value or Reset to clear the form.

About this blood sugar converter

The blood sugar converter switches a glucose reading between the two standard clinical units. The U.S. and a few other countries report glucose in mg/dL, while most of the rest of the world reports it in mmol/L; the conversion factor is the molar mass of glucose: 1 mmol/L = 18.0182 mg/dL.

Conversion is bidirectional and exact: mg/dL = mmol/L × 18.0182, mmol/L = mg/dL ÷ 18.0182. When you pick a reading context (fasting or post-meal), the tool also maps the value against the American Diabetes Association Standards of Care reference ranges: fasting < 100 mg/dL is normal, 100–125 mg/dL is prediabetes, ≥ 126 mg/dL is in the diabetes range; for 2-hour post-meal those cut-offs are 140 and 200 mg/dL.

Worked example: a fasting reading of 110 mg/dL ÷ 18.0182 ≈ 6.1 mmol/L. By the ADA fasting reference range that value falls in the prediabetes band — which is a screening category, not a diagnosis.

This converter uses static ADA Standards of Care reference ranges and is not a substitute for advice from a qualified clinician. This calculator is for general educational purposes only and is not medical advice — consult a licensed healthcare professional for personal guidance.

FAQ

What is the exact conversion factor?: 1 mmol/L of glucose equals 18.0182 mg/dL. It comes from the molar mass of glucose (180.156 g/mol) and the standard 1/10 ratio between mg/dL and mg/L.
Which countries use which unit?: The U.S., Japan, and some others use mg/dL. Most of Europe, the UK, Canada, Australia, and much of the rest of the world use mmol/L.
Why does the reference band depend on context?: A perfectly healthy person’s glucose rises after a meal. The ADA publishes separate cut-offs for fasting (≥ 8 h) and 2-hour post-meal readings; we don’t assign a band to random readings because the expected range is too wide.
Does a single reading mean I have diabetes?: No. The ADA requires repeat confirmatory testing — and clinicians look at HbA1c plus symptoms, not one finger-stick. Use the band as context, not a diagnosis.
Is my reading stored anywhere?: No. The converter runs entirely in your browser.