Understanding mg/dL vs mmol/L is essential if you compare blood glucose readings from different countries, travel with diabetes, or use a meter bought abroad. These are the two standard blood glucose units worldwide — and mixing them up can make a normal reading look alarming, or vice versa.
In the UK, the NHS reports blood sugar in mmol/L (millimoles per litre). If you see results in mg/dL — common on US websites, apps, or imported meters — use the conversion table below before comparing against your care plan. If you buy a meter online, confirm on the Betachek store (UK) that the device and units match UK practice. Your GP or diabetes team can confirm the targets that apply to you.
Blood glucose meters such as the Betachek C50 are factory set to display either mg/dL or mmol/L. Before you rely on a reading, confirm your meter matches the units your doctor or diabetes team uses — especially if you have switched devices or bought one online from another region.
Blood Glucose Units by Country: mg/dL vs mmol/L
Blood glucose (blood sugar) is measured using two main units depending on the country:
- mg/dL (milligrams per decilitre) — primarily used in the United States and several other countries.
- mmol/L (millimoles per litre) — the modern SI unit used in the UK, Ireland, Australia, Canada, and most of Europe.
| Country | Unit of Measurement |
|---|---|
| Algeria | mg/dL |
| Argentina | mg/dL |
| Australia | mmol/L |
| Austria | mg/dL |
| Bangladesh | mg/dL |
| Belgium | mg/dL |
| Brazil | mg/dL |
| Canada | mmol/L |
| Chile | mg/dL |
| China | mmol/L |
| Colombia | mg/dL |
| Croatia | mmol/L |
| Cyprus | mg/dL |
| Czech Republic | mmol/L |
| Denmark | mmol/L |
| Ecuador | mg/dL |
| Egypt | mg/dL |
| Finland | mmol/L |
| France | mg/dL |
| Georgia | mg/dL |
| Germany | Both (mmol/L & mg/dL) |
| Greece | mg/dL |
| Hong Kong | mmol/L |
| Hungary | mmol/L |
| Iceland | mmol/L |
| India | mg/dL |
| Indonesia | mg/dL |
| Iran | mg/dL |
| Ireland | mmol/L |
| Israel | mg/dL |
| Italy | mg/dL |
| Jamaica | mmol/L |
| Japan | mg/dL |
| Jordan | mg/dL |
| Kazakhstan | mmol/L |
| Latvia | mmol/L |
| Lebanon | mg/dL |
| Lithuania | mmol/L |
| Malaysia | mmol/L |
| Malta | mmol/L |
| Mexico | mg/dL |
| Netherlands | mmol/L |
| New Zealand | mmol/L |
| Norway | mmol/L |
| Peru | mg/dL |
| Poland | mg/dL |
| Portugal | mg/dL |
| Russia | mmol/L |
| Slovakia | mmol/L |
| Slovenia | mmol/L |
| South Africa | mmol/L |
| South Korea | mg/dL |
| Spain | mg/dL |
| Sweden | mmol/L |
| Switzerland | mmol/L |
| Syria | mg/dL |
| Taiwan | mg/dL |
| Thailand | mg/dL |
| Tunisia | mg/dL |
| Turkey | mg/dL |
| United Arab Emirates | mg/dL |
| United Kingdom | mmol/L |
| United States | mg/dL |
| Uruguay | mg/dL |
| Venezuela | mg/dL |
| Yemen | mg/dL |
Blood Glucose Units in the UK (mmol/L)
The United Kingdom uses mmol/L for blood glucose results in the NHS, GP surgeries, and hospital labs. Typical fasting targets for many adults with type 2 diabetes are around 4–7 mmol/L before meals, though your clinician may set different goals. For official guidance on blood sugar ranges, see the NHS diabetes information pages. The Betachek C50 uses 50-test cassettes (order cassettes) and is available from the Betachek store (UK).
How to Convert mg/dL vs mmol/L
Use this simple formula whenever you need to switch between mg/dL vs mmol/L:
- mg/dL → mmol/L: divide the value by 18
- mmol/L → mg/dL: multiply the value by 18
Example: 126 mg/dL ÷ 18 = 7.0 mmol/L
Important Notes
- Germany is the main exception — both units are commonly used in clinical practice depending on the region.
- Most blood glucose meters — including the Betachek C50 — are factory set to mg/dL or mmol/L — check the display before comparing readings.
- Always follow your local medical guidelines and device instructions.
Order the meter or compatible cassettes from the Betachek store (UK) or the Betachek C50 and 50-test cassettes page.
Why are mg/dL and mmol/L both still used?
Blood glucose is reported in two different units — mg/dL and mmol/L — even though both are metric, because of differences in how countries adopted scientific standards. mg/dL (milligrams per decilitre) is the older, conventional unit that measures the mass of glucose in a volume of blood. It remains the standard in the United States and a few other countries. mmol/L (millimoles per litre), on the other hand, is the modern SI unit that measures the actual number of glucose molecules per litre of blood. Most countries around the world switched to mmol/L for greater scientific consistency and international standardisation. The United States largely retained the traditional mg/dL unit in clinical practice, which is why both systems continue to exist today.
Related blood glucose guides
- How to use a blood glucose monitoring system
- Best blood glucose meter in the UK — 2026 guide
- Are all blood glucose meters the same?
- Betachek C50 50-test cassettes — UK store
Source: Compiled from international medical references and diabetes health organisations (2026).