Medical disclaimer: GlucoseForge is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Device Comparison·20 min read·Updated 2026·All major devices covered
The CGM market has expanded dramatically. There are now prescription devices for diabetes management, over-the-counter options for wellness use, and closed-loop systems that automatically dose insulin. This guide covers every major device — what it does, who it's for, and what it costs.
Overview
The CGM market in 2026
The CGM device market has split into two distinct segments: prescription medical devices for diabetes management, and over-the-counter wellness devices for people without diabetes who want metabolic insights. Understanding which segment you belong to is the first step in choosing the right device.
Prescription CGMs — Dexcom G7, Abbott FreeStyle Libre 3, Medtronic Guardian 4 — are approved for diabetes management and meet the clinical accuracy standards required for insulin dosing decisions. They require a prescription in most countries and are covered by insurance for eligible patients.
OTC CGMs — Dexcom Stelo and Abbott Lingo — are FDA-cleared for adults without diabetes and available without a prescription at pharmacies and online. They use similar sensor technology but are designed as wellness tools rather than medical devices, with software optimized for behavioral insights rather than clinical management.
Transparency note: Links on this page may include affiliate referral codes. GlucoseForge may receive a commission if you purchase through these links, at no additional cost to you. Our editorial assessments are independent and not influenced by commercial relationships.
Which category are you?
If you have diabetes (Type 1 or Type 2) or prediabetes, talk to your healthcare provider before choosing a CGM. Prescription devices are covered by insurance for many patients, making them significantly more affordable than OTC options. If you do not have diabetes and are interested in metabolic health monitoring, OTC devices are designed for you and are available without a medical appointment.
Prescription CGM
Prescription devices for diabetes
📡
Dexcom G7
Dexcom · Prescription required
PrescriptionType 1Type 2Closed-loop compatible
The Dexcom G7 is the benchmark prescription CGM against which other devices are measured. This entry covers the original 10-day G7 (8.2% MARD); Dexcom's newer G7 15 Day variant (8.0% MARD, ~15.5-day wear including grace period) is now the recommended variant for most adults as of late 2025 — check with your prescriber which one you'll receive. Significantly smaller than its predecessor (the G6), it integrates the sensor and transmitter into a single disposable unit — simplifying the system and reducing the profile on the body. It supports direct-to-Apple-Watch display without a phone intermediary, and is compatible with major automated insulin delivery (AID) systems.
10 days
Wear time
8.2%
MARD accuracy
2hr
Warm-up time
Check price
With insurance
Strengths
Smallest all-in-one design on the market
Direct Apple Watch display (no phone needed)
Widest AID system compatibility
30-minute grace period after 10-day sensor expiry
Strong insurance coverage in US
Excellent app with pattern insights
Limitations
Original 10-day wear is shorter than Libre 3's 14 days (Dexcom's newer G7 15 Day variant closes this gap)
Higher out-of-pocket cost without insurance
Abdomen and upper arm placement only
Requires prescription
Best for
As an Amazon Associate we earn from qualifying purchases. Some links on this page are affiliate links.
People with Type 1 diabetes using or considering closed-loop insulin delivery. Also excellent for Type 2 patients on insulin who want the most comprehensive data and Apple Watch integration. The reference standard for clinical CGM in 2026. Read the full Dexcom G7 review →
The FreeStyle Libre 3 combines the world's smallest CGM sensor with 14-day wear and real-time Bluetooth streaming, and reports a 7.8% MARD. Abbott's newer FreeStyle Libre 3 Plus variant extends wear to about 15 days and is being positioned as the current standard for many new prescriptions; its MARD has not been independently confirmed as distinct from the original Libre 3's figure. It delivers readings every minute — more frequently than Dexcom's five-minute interval. Abbott's LibreLink app includes a comprehensive data analysis platform and the LibreLinkUp companion app for real-time sharing with caregivers.
14 days
Wear time
7.8%
MARD accuracy
60min
Warm-up time
Check price
With insurance
Strengths
Longest wear time of major prescription CGMs (14 days)
Highest published MARD accuracy (7.8%)
World's smallest sensor form factor
1-minute reading interval (vs 5 min for Dexcom)
Shorter warm-up time (60 min vs 2hr)
Often lower cost with insurance than Dexcom
Limitations
Limited closed-loop AID compatibility vs Dexcom
No direct Apple Watch display
Upper arm placement only
Requires prescription
Best for
People with Type 2 diabetes and those prioritizing accuracy and sensor longevity. The 14-day wear and best-in-class MARD make it the leading choice for patients not using closed-loop AID systems. Often the more economical prescription option. Read the full FreeStyle Libre 3 review →
The Guardian 4 is Medtronic's current CGM sensor, designed primarily for use with Medtronic's MiniMed insulin pump systems in a closed-loop configuration. It offers factory calibration and 7-day wear. The Guardian 4 is best understood as a component of the Medtronic closed-loop ecosystem rather than a standalone CGM — its strengths lie in integration with Medtronic pumps rather than standalone use.
7 days
Wear time
8.8%
MARD accuracy
2hr
Warm-up time
Varies
With insurance
Strengths
Deep integration with Medtronic pump ecosystem
Proven closed-loop algorithm (780G system)
Factory calibrated — no finger-sticks required
Limitations
Shortest wear time of major CGMs (7 days)
Higher MARD than Dexcom and Libre
Best suited for Medtronic pump users only
Limited standalone app functionality
Best for
Existing Medtronic MiniMed pump users who want closed-loop functionality within the Medtronic ecosystem. Not recommended as a first-choice standalone CGM given shorter wear time and lower accuracy versus competitors.
Dexcom Stelo was the first FDA-cleared OTC CGM device, launched in 2024. It uses the same core sensor technology as the G7 but is FDA-cleared for adults 18+ who do not use insulin, including people with Type 2 diabetes managed without insulin, prediabetes, and those without any diagnosis seeking metabolic insights. The Stelo app focuses on behavioral insights — showing how specific foods, activities, and sleep affect glucose — rather than clinical management features. Available at major pharmacies and online without a prescription.
15 days
Wear time
~7.3–9.1%
MARD accuracy
No Rx
Availability
Check price
Retail price
Strengths
No prescription required — available at CVS, Walgreens, Amazon
15-day wear — longer than prescription G7
Dexcom sensor reliability and quality
App designed for behavioral insights and habit change
Food logging with glucose response correlation
Apple Health and Google Health integration
Limitations
Not for insulin users — Rx G7 required
No low glucose alerts (not cleared for alarm use)
Not covered by insurance as wellness device
Higher cost than Rx with insurance coverage
Best for
The leading OTC CGM choice for people without diabetes interested in metabolic health, as well as non-insulin-using Type 2 patients who cannot get insurance coverage for prescription CGM. Dexcom's brand reliability and 15-day sensor are significant advantages over the prescription G7's 10-day wear. Read the full Dexcom Stelo review →
Abbott Lingo is Abbott's OTC CGM, built on the FreeStyle Libre sensor platform and cleared for adults without diabetes. The Lingo system emphasizes coaching and habit formation — the app provides personalized glucose coaching, tracks "Lingo Points" (a proprietary glucose stability score), and offers meal and activity recommendations. Like the Libre 3, it achieves high sensor accuracy and offers 14-day wear. Available without prescription at major retailers.
14 days
Wear time
~8.1–10.7%
MARD accuracy
No Rx
Availability
Check price
Retail price
Strengths
Slightly lower cost than Stelo
Built-in glucose coaching and recommendations
Built on the FreeStyle Libre sensor platform
14-day wear — competitive with Stelo
Lingo Points score makes data accessible to non-technical users
Limitations
Coaching model may feel prescriptive for some users
Less raw data access than Stelo for advanced users
Upper arm placement only
Not covered by insurance
Best for
People new to CGM who want guided coaching rather than raw data. The Lingo Points system and built-in recommendations make it more accessible for people who find CGM data overwhelming. Slightly more affordable than Stelo with comparable sensor performance. Read the full Abbott Lingo review →
The Eversense E3 is an implantable CGM lasting 6 months before replacement. Senseonics/Ascensia's newer Eversense 365 extends this to a full 12 months (8.8% MARD per the ENHANCE study) and is now available alongside E3 rather than replacing it. A small sensor is implanted subcutaneously by a healthcare provider in an office procedure. The external smart transmitter is worn over the implant site and can be removed for swimming or charging. On-body vibration alerts (the transmitter vibrates on the skin) provide alerts without a phone in range.
180 days
Wear time
~9.1%
MARD accuracy
Office Rx
Requires implant
Varies
Insurance dependent
Strengths
6-month wear — eliminates frequent sensor changes
On-body vibration alerts without phone
Removable transmitter for swimming, charging
No adhesive patch irritation
Ideal for people with adhesive allergies
Limitations
Requires minor surgical procedure for insertion and removal
Lower accuracy than Dexcom and Libre
Limited availability of trained inserting providers
Not compatible with AID systems
Higher cost per year than disposable sensors
Best for
People who find frequent sensor changes burdensome, have adhesive allergies or skin sensitivities, or have an active lifestyle where a removable transmitter is advantageous. A niche but genuinely useful option for the right patient profile.
Broadest closed-loop compatibility, best app ecosystem, and the reference standard for intensive insulin management. Work with your endocrinologist to confirm insurance coverage and AID system compatibility.
If you have Type 2 diabetes on insulin
FreeStyle Libre 3
Best accuracy, longest wear, and often the most affordable prescription option with insurance. Excellent for patients who want reliable glucose data without closed-loop complexity.
If you have Type 2 not on insulin or prediabetes
Ask your doctor first
Coverage has expanded significantly. Many patients in this category now qualify for prescription CGM coverage. If covered, a prescription device gives better clinical features than OTC options. If not covered, Stelo or Lingo are practical alternatives.
If you don't have diabetes but want metabolic insights
Dexcom Stelo or Abbott Lingo
Both are designed for you. Choose Stelo if you want raw data and more flexibility. Choose Lingo if you want guided coaching and a simpler experience. Both are available without a prescription at major pharmacies.
If you have adhesive allergies or dislike sensor changes
Eversense E3
The 6-month implantable sensor eliminates both the adhesive patch and frequent sensor changes. Requires a minor office procedure but offers the most convenient long-term monitoring experience once implanted.
If you use a Medtronic insulin pump
Medtronic Guardian 4
Deep integration with the MiniMed 780G closed-loop system makes Guardian 4 the natural choice for Medtronic pump users. The closed-loop algorithm compensates for the lower standalone CGM accuracy within the integrated system.
Always consult your healthcare provider
CGM device selection for diabetes management should be made with your endocrinologist or diabetes care provider. Insurance coverage, AID system compatibility, and your specific clinical situation all affect which device is right for you. This guide provides general information — not personalized medical advice.
Subscription platforms
CGM subscription platforms — app + sensor bundles
Beyond standalone devices, several platforms bundle CGM sensors with proprietary analytics apps and coaching. See individual pricing pages for full breakdowns:
The US CGM market is dominated by two companies — Dexcom and Abbott — who together account for the substantial majority of devices in active use. Medtronic holds a smaller share concentrated among users of its integrated pump systems.
Company
Primary device
US market position
Key segment
Dexcom
G7, Stelo
Largest CGM revenue share (US)
Type 1, Type 2 insulin, OTC wellness
Abbott
FreeStyle Libre 3, Lingo
Largest global CGM unit volume
Type 2, international markets, OTC wellness
Medtronic
Guardian 4
Integrated pump systems
Closed-loop AID users
Senseonics
Eversense E3
Niche — implantable
Patients seeking 180-day wear
OTC market (2025–2026): The OTC CGM segment — devices available without a prescription — opened in 2024 with FDA clearance of the Dexcom Stelo and Abbott Lingo. This segment is growing rapidly as wellness-focused consumers discover CGM outside the traditional diabetes care pathway.
Key trend: Abbott's FreeStyle Libre platform has driven CGM adoption globally through lower pricing and broader pharmacy availability. Dexcom maintains premium positioning based on accuracy leadership in the hypoglycemic range and broader AID system compatibility.
Full specifications
Complete CGM specifications — all devices 2026
Sensor specifications
Device
Wear time
Reading interval
Calibration
Waterproof rating
Warm-up time
Dexcom G7 15 Day
~15.5 days
Every 5 min
None required
8ft / 24hr
30 min
Dexcom G7 (10 Day)
10 days
Every 5 min
None required
8ft / 24hr
30 min
FreeStyle Libre 3
14 days
Every 1 min
None required
1m / 30min
60 min
FreeStyle Libre 3 Plus
~15 days
Every 1 min
None required
1m / 30min
60 min
Medtronic Guardian 4
7 days
Every 5 min
None required
IPX7
2 hours
Dexcom Stelo
15 days
Every 5 min
None required
8ft / 24hr
30 min
Abbott Lingo
14 days
Every 1 min
None required
1m / 30min
60 min
Eversense 365
365 days
Every 5 min
2x daily
IP68
24 hours
Eversense E3
180 days
Every 5 min
2x daily
IP68
24 hours
Accuracy (MARD) by device
MARD — Mean Absolute Relative Difference — is the standard CGM accuracy metric. Lower is more accurate. All figures from manufacturer pivotal trial publications.
Device
Overall MARD
Source
Study population
Dexcom G7 15 Day
8.0%
Dexcom pivotal trial (2025)
Adults with diabetes
FreeStyle Libre 3
7.8%
Abbott pivotal trial
Adults with diabetes
FreeStyle Libre 3 Plus
Not independently published
Abbott (distinct figure not confirmed)
Adults with diabetes
Abbott Lingo
8.1–10.7%
FDA 510(k) K233655
Adults with diabetes (Libre 2 data)
Dexcom G7 (10 Day)
8.2%
Dexcom pivotal trial
Adults and children with diabetes
Dexcom Stelo
7.3–9.1%
FDA 510(k) K234070
Adults 18+ not using insulin
Medtronic Guardian 4
8.8%
Medtronic pivotal trial
Adults with diabetes
Eversense 365
8.8%
ENHANCE study (Bailey et al. 2025)
Adults with diabetes
Eversense E3
9.1%
PROMISE trial
Adults with diabetes
US retail pricing 2026
Device
Retail price / month
With insurance
Prescription required
Abbott Lingo
Check price
Not covered (OTC wellness)
No
Dexcom Stelo
Check price
Not covered (OTC wellness)
No
FreeStyle Libre 3
Check price
Often covered — copay varies
Yes
FreeStyle Libre 3 Plus
Check price
Often covered — copay varies
Yes
Dexcom G7 (10 Day)
Check price
Often covered — copay varies
Yes
Dexcom G7 15 Day
Check price
Often covered — copay varies
Yes
Medtronic Guardian 4
Varies
Often covered with pump
Yes
Eversense 365
Varies
Limited coverage
Yes + procedure
Eversense E3
Varies
Limited coverage
Yes + procedure
App and connectivity
Device
iOS
Android
Apple Watch
Data export
AID compatible
Dexcom G7 15 Day
Yes
Yes
Yes (direct)
CSV + Clarity
Yes — multiple systems
Dexcom G7 (10 Day)
Yes
Yes
Yes (direct)
CSV + Clarity
Yes — multiple systems
FreeStyle Libre 3
Yes
Yes
Via iPhone
PDF + CSV
Limited
FreeStyle Libre 3 Plus
Yes
Yes
Via iPhone
PDF + CSV
Limited
Dexcom Stelo
Yes
Yes
Via iPhone
CSV + Clarity
No
Abbott Lingo
Yes
Yes
Via iPhone
Limited
No
Medtronic Guardian 4
Yes
Yes
No
CareLink
Medtronic only
Eversense 365
Yes
Yes
No
Limited
No
Eversense E3
Yes
Yes
No
Limited
No
FAQ
Frequently asked questions
What is the CGM market share in the United States in 2025–2026?
The US CGM market is dominated by Dexcom and Abbott. Dexcom holds the largest revenue share in the US market, driven by the G7 and the newer OTC Stelo device. Abbott leads in global unit volume through its FreeStyle Libre platform and has expanded into the OTC wellness market with Abbott Lingo. Medtronic holds a smaller US share concentrated among users of its integrated closed-loop pump systems. The overall CGM market is growing rapidly, driven by expanded insurance coverage, OTC availability, and increasing wellness adoption by people without diabetes.
What is the difference between Dexcom and Abbott CGM devices?
Dexcom (G7, Stelo) and Abbott (FreeStyle Libre 3, Lingo) are the two dominant CGM platforms. Key differences: Dexcom G7 has broader AID (automated insulin delivery) compatibility and direct Apple Watch display; Abbott Libre 3 (7.8% MARD) and Dexcom's newer G7 15 Day (8.0% MARD) now report the closest published single MARD figures, both ahead of the original 10-day G7 (8.2% MARD). Libre 3's 14-day wear and G7 15 Day's ~15.5-day wear are now comparable, versus the original G7's 10 days. For OTC devices: Abbott Lingo is typically cheaper than Dexcom Stelo, but Stelo's published MARD range (7.3–9.1%) is lower than Lingo's (8.1–10.7%). Both use factory calibration and require no fingerstick confirmation.
Which CGM device is most accurate in 2026?
Based on published MARD data from pivotal trials: Dexcom G7 15 Day (8.0%) and FreeStyle Libre 3 (7.8%) currently report the closest, best-documented single MARD figures; FreeStyle Libre 3 Plus's MARD is not yet independently confirmed as distinct from Libre 3's own figure. The original 10-day G7 (8.2%), Medtronic Guardian 4 (8.8%), Eversense 365 (8.8%), and Eversense E3 (9.1%) follow. Dexcom Stelo (7.3–9.1%) and Abbott Lingo (8.1–10.7%) report ranges that aren't directly comparable to single figures or to each other's trials. Lower MARD = more accurate, but MARD is measured in controlled clinical studies — real-world accuracy depends on sensor placement, activity level, and individual variation. See our full CGM accuracy comparison for details.
What CGM devices are available without a prescription in the US?
As of 2026, two CGM devices are FDA-cleared for over-the-counter sale in the United States without a prescription: the Dexcom Stelo and the Abbott Lingo. Both are available at major retailers and pharmacies. They are cleared for use by people without insulin-treated diabetes. Prescription CGMs (Dexcom G7 and G7 15 Day, FreeStyle Libre 3 and Libre 3 Plus, Medtronic Guardian 4) require a valid prescription and are typically covered by insurance for qualifying patients.
Technically yes — prescription CGMs can be obtained with a prescription for off-label use. However, OTC devices (Stelo, Lingo) are specifically designed and priced for wellness use, offer comparable sensor technology, and do not require a medical appointment. For most people without diabetes, OTC CGM is the more practical and economical path. Note that OTC devices are not cleared for insulin dosing decisions and should not be used as substitutes for prescription devices in people with diabetes who require insulin.
Does insurance cover CGM?
Coverage has expanded significantly. Medicare covers CGM for all patients with diabetes who use insulin. Most private insurance plans cover prescription CGM for patients with Type 1 diabetes and for Type 2 patients on insulin; coverage for non-insulin Type 2 patients is improving but variable. OTC devices (Stelo, Lingo) are not covered by insurance as they are classified as wellness devices. Prior authorization requirements vary by insurer — your provider's office can help navigate coverage requirements and submit necessary documentation.
Is Dexcom G7 better than FreeStyle Libre 3?
It depends on the variant. Against the original 10-day G7 (8.2% MARD), Libre 3 has a slight accuracy edge (7.8% MARD) and longer wear (14 vs 10 days). But Dexcom's newer G7 15 Day variant reports 8.0% MARD and ~15.5-day wear — nearly matching Libre 3 on both counts. The G7 has broader closed-loop AID compatibility and direct Apple Watch display regardless of variant. For most Type 2 patients not using closed-loop therapy, Libre 3 remains a strong choice; for Type 1 patients considering or using AID systems, G7's compatibility is more important. Both are excellent devices.
How long does it take to get used to wearing a CGM?
Most people adapt quickly — within one to two sensor changes (2–4 weeks). The initial adjustment involves learning to apply sensors correctly, managing the adhesive patch during activities and bathing, and learning to interpret the data the device provides. Physically, sensor wear is rarely noticeable after the first day. The larger adjustment is cognitive — learning to respond calmly to glucose fluctuations rather than reacting to every individual reading. Most users report that CGM becomes second nature within a month.
Are OTC CGMs as accurate as prescription devices?
For wellness monitoring purposes, yes — OTC CGMs use the same core sensor technology as prescription devices and achieve similar MARD values. The difference is not in sensor accuracy but in the clinical features: OTC devices lack low glucose alarms approved for hypoglycemia alerting, are not cleared for insulin dosing decisions, and are not compatible with closed-loop AID systems. For tracking metabolic health, food responses, and general glucose patterns, OTC CGM accuracy is more than sufficient.