Dexcom has officially launched the G7 15-Day continuous glucose monitor, giving people with diabetes an extended-wear option that halves the number of sensor changes per month. The device received FDA clearance in late 2024 and began shipping to U.S. pharmacies in early 2025, priced identically to the standard 10-day G7 on a per-month basis.
Same Accuracy, Fewer Insertions
The G7 15-Day sensor uses the same electrochemical sensing technology as the original G7 and maintains the same overall MARD (Mean Absolute Relative Difference) of 8.2 percent in clinical trials. MARD is the gold-standard accuracy metric for continuous glucose monitors—lower numbers indicate better agreement with fingerstick blood glucose readings. At 8.2 percent, the G7 15-Day matches Abbott's Libre 3 Plus in head-to-head accuracy.
What changes is wear duration. Standard G7 sensors last 10 days, requiring roughly 3 sensor changes per month. The 15-Day variant reduces that cadence to 2 changes per month, meaning fewer insertions, less adhesive waste, and a more seamless user experience. Dexcom reports that the 15-Day sensor uses a reformulated enzyme layer that maintains signal stability over the longer wear period without degradation.
How It Differs from Standard G7
Physically, the G7 15-Day sensor is the same compact size—about 30 percent smaller than the G6—and uses the same one-piece applicator. The 30-minute warmup period is unchanged. Bluetooth 5.0 connectivity, 5-minute reading intervals, and real-time sharing through the Dexcom Follow app remain identical. The key engineering difference is internal: a modified glucose-oxidase membrane designed to resist biofouling for an additional 5 days.
Users can still stack a new sensor on top of the old one (start the new sensor before removing the expired one) to eliminate gaps in glucose data—a practice Dexcom calls "sensor overlap."
Competitive Positioning
The 15-day wear time directly matches Abbott's FreeStyle Libre 3 Plus, which also offers 15-day wear. This eliminates one of the few practical advantages Libre held over the G7 lineup. Both devices now deliver:
- 15-day wear duration - Sub-9 percent MARD - Real-time smartphone connectivity - No fingerstick calibrations required
Where the G7 15-Day retains an edge is in insulin pump integration. Dexcom's G7 platform remains the sensor of choice for automated insulin delivery systems, including the Omnipod 5 and Tandem Mobi pumps. Abbott's Libre sensors are not currently integrated with any insulin pump on the U.S. market.
What This Means for Existing G7 Users
Current Dexcom G7 users can switch to the 15-Day variant with no hardware changes—the same transmitter-free design applies. Insurance formulary placement may vary; patients should verify with their pharmacy benefits manager. For those paying out of pocket, the monthly cost remains approximately $75-$100 per month with a manufacturer savings card, because Dexcom ships two 15-Day sensors per monthly order instead of three 10-Day sensors.
The G7 15-Day cements Dexcom's position in the premium CGM segment while addressing the most common user complaint: too-frequent sensor swaps.
