Continuous glucose monitors (CGMs) have revolutionized diabetes management, giving users real-time blood sugar data without constant fingersticks. Two of the most popular CGMs today are the Dexcom G7 and the Freestyle Libre 3. Which one is better for you?

Sensor Size & Wear Time

The Dexcom G7 is 60% smaller than its predecessor and wears for 10 days plus a 12-hour grace period. The Freestyle Libre 3 is the smallest CGM on the market — about the size of two pennies — and wears for 14 days.

Real-Time Alerts

Both CGMs now offer real-time glucose alerts directly to your smartphone. The Dexcom G7 will alert you even if your sugar drops dangerously low overnight. The Libre 3 also sends real-time alerts — a major upgrade from the Libre 2 which required manual scanning.

Accuracy

The Dexcom G7 has a MARD of 8.2%, while the Freestyle Libre 3 has a MARD of 7.8%, making the Libre 3 slightly more accurate on paper — though both perform excellently in real-world use.

Warm-Up Time

Dexcom G7 has a 30-minute warm-up period. Freestyle Libre 3 requires 60 minutes. If you frequently change sensors, the G7’s faster startup is a practical advantage.

Cost & Insurance

Both are covered by Medicare, Medicaid, and most private insurance for qualifying patients. The Freestyle Libre 3 tends to be more affordable without insurance, making it more accessible for uninsured patients.

Pump Integration

The Dexcom G7 integrates with a wider ecosystem including Apple Watch, Garmin, and automated insulin delivery systems like Tandem t:slim X2 and Omnipod 5. If you use an insulin pump, Dexcom is usually the better choice.

Which CGM Should You Choose?

Choose Dexcom G7 if: You use an insulin pump, want wider device integration, or need faster warm-up time.

Choose Freestyle Libre 3 if: You want the smallest sensor, need 14-day wear, or are cost-conscious without insurance.

Disclaimer: Consult your healthcare provider before switching or starting a CGM device.