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Getting Started

What is a sensor code and why do I need one?

Last Updated · September 28, 2021

A sensor code allows you to use the Dexcom ONE CGM System without the need for fingersticks or calibrations.* When you start a new sensor, you must enter a code into your display device, either manually or by taking a photo, as each sensor has its own code printed on the back of the adhesive patch.

How to scan Dexcom sensor code using phone

Do not use a code from a different sensor or make up a code. If you do, your sensor will not work as well and could display inaccurate data.

* Fingersticks required for diabetes treatment decisions if symptoms or expectations do not match readings.

Related Questions

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5-step learning journey

Discover education resources, organised in a 5-step journey, to learn key information about your Dexcom ONE CGM system, from getting started, your first 10 days, to using Dexcom ONE in the long run.

Step 1: The basics of CGM
Step 2: Getting started
Step 3: Your first 10 days
Step 4: Using Dexcom ONE in the long run
Step 5: Understand your Diabetes trends