The two most widely prescribed CGMs in 2026 head to head. Both are factory-calibrated, prescription-only devices — but they differ meaningfully on accuracy, sensor life, cost, and AID compatibility.
Note: this comparison covers the original 10-day Dexcom G7 and the original 14-day FreeStyle Libre 3. Dexcom G7 15 Day (8.0% MARD, ~15.5-day wear) is now the recommended adult variant, and Abbott FreeStyle Libre 3 Plus (15-day wear) is Abbott's newer variant of Libre 3. See our most accurate CGM comparison for the current full lineup.
Medical Disclaimer: This content is for informational purposes only. Always consult your healthcare provider before making health decisions.
FreeStyle Libre 3 wins on accuracy and cost. Dexcom G7 wins on AID system compatibility and Apple Watch integration. For most users without AID systems, the Libre 3 is the better value at $130/month vs G7's $350/month retail.
| Attribute | Dexcom G7 | FreeStyle Libre 3 |
|---|---|---|
| MARD accuracy | 8.2% | 7.8% |
| Sensor life | 10 days (15 days on newer G7 15 Day) | 14 days (15 days on newer Libre 3 Plus) |
| Reading interval | Every 5 min | Every 1 min |
| Calibration required | None | None |
| Warm-up time | 30 min | 60 min |
| Retail price/month | Check price | Check price |
| With insurance | Often $0–50 | Often $0–40 |
| Prescription required | Yes | Yes |
| Apple Watch display | Yes — direct | Via iPhone only |
| AID system compatibility | Broad (multiple systems) | Limited |
| Waterproof rating | 8ft / 24hr | 1m / 30min |
| App | Dexcom G7 + Clarity | LibreLink + LibreLinkUp |
| Data sharing | Dexcom Follow (unlimited) | LibreLinkUp (up to 20) |
| Sensor wear location (US) | Back of upper arm (ages 7+); upper buttocks alternative for ages 2–6. Abdomen is not an approved G7 site in the US. | Back of upper arm only |
G7 vs Libre 3 vs every other device — with or without insurance.
FreeStyle Libre 3 posts a MARD of 7.8% versus the Dexcom G7's 8.2% — a small but consistent difference in clinical trials. More significantly, Libre 3 reads every minute (versus every 5 minutes for the G7), giving a smoother, more granular glucose curve that better captures rapid post-meal rises and drops.
In practice, both devices are highly accurate for clinical decision-making. The MARD gap becomes most relevant in edge cases — rapid glucose fluctuations, hypoglycemic ranges, and situations where trending accuracy matters most. For most users, the difference is not clinically significant. Note that Dexcom's newer G7 15 Day variant reports 8.0% MARD — closer to Libre 3's 7.8% than the original 10-day G7's 8.2%.
At retail, Dexcom G7 costs approximately $350/month versus $130/month for FreeStyle Libre 3 — a significant difference. With insurance, both devices are commonly covered for qualifying patients, often reducing costs to $0–50/month. If you have coverage for both, check your specific plan formulary — the insured cost difference may be minimal.
Without insurance, Libre 3 is substantially cheaper. See our full Dexcom cost without insurance guide and FreeStyle Libre cost guide for detailed pricing options.
For users on automated insulin delivery (AID) systems — closed-loop systems that automatically adjust basal insulin — Dexcom G7 is the clear choice. G7 is compatible with multiple AID platforms including Tandem Control-IQ, Omnipod 5, and others. FreeStyle Libre 3 has limited AID compatibility as of 2026.
If you use or plan to use an AID system, Dexcom G7 is the only practical choice of these two.
Tandem Control-IQ, Omnipod 5, and most other closed-loop systems require Dexcom. G7 also gives direct Apple Watch display and broader wear location options. If AID compatibility is not a factor, Libre 3 offers better value.
Read full Dexcom G7 review →Libre 3 posts a well-documented 7.8% MARD (close to, though not below, G7 15 Day's newer 8.0% figure), reads every minute, lasts 14 days, and costs significantly less at retail. For most users not on AID systems, it is the stronger value choice.
Read full FreeStyle Libre 3 review →Every device side by side — 30, 90, or 365 days.
Accuracy, cost, sensor life, and who each device is best for — all in one place.
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