TCRThe Comparison Report

GPS Running Watches / COROS APEX 4 (42mm) vs Garmin Instinct 3 Solar (45mm)

COROS APEX 4 (42mm) vs Garmin Instinct 3 Solar (45mm)

Best Overall

COROS APEX 4 (42mm)

Free offline topo maps and a titanium bezel for $429 — with a screen you fight in low light.

Wins overall by 0.7 points

Buy on Amazon

Quick Verdict

The COROS APEX 4 (42mm) takes this by a clear 0.7 points. Free offline topo maps and a titanium bezel for $429 — with a screen you fight in low light. The Garmin Instinct 3 Solar (45mm) only makes sense if it wins on a category you care about more than the total.

The COROS APEX 4 (42mm) and Garmin Instinct 3 Solar (45mm) are both current-generation GPS Running Watch models, and the Garmin Instinct 3 Solar (45mm) is $29 cheaper than the COROS APEX 4 (42mm) ($399.99 vs $429). On Navigation & Maps, the COROS APEX 4 (42mm) leads (7.8 vs 2.8/10) — real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch.. On Value, the COROS APEX 4 (42mm) leads (8.6 vs 7.0/10) — what the watch delivers per dollar against everything else in the comparison at the moment of purchase.. On GPS Accuracy, the Garmin Instinct 3 Solar (45mm) leads (8.6 vs 8.0/10) — trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.. Overall, the COROS APEX 4 (42mm) scores 7.9/10 across our 8 scoring categories versus 7.2/10 for the Garmin Instinct 3 Solar (45mm). Below, we break down the full spec sheet, category-by-category scores, and exactly who should buy which one.

Side-by-Side Comparison

SpecCOROS APEX 4 (42mm)Garmin Instinct 3 Solar (45mm)
Price$429.00$399.99
Release Year20252025
Display1.2-in 240x240 3rd-gen transflective MIP, always-on, no AMOLED battery penalty — but DC Rainmaker and Tom's Guide both call it dim indoors and in low lightMonochrome 176x176 transflective MIP, always-on by design, no touchscreen — readable in direct sun and costs almost nothing to leave on
Smartwatch Battery ( days)1528
Always-On Display CostNo always-on penalty — the MIP screen is permanently on. (The 46 mm version is rated 24 days smartwatch and 65 h all-systems GPS if you want the bigger numbers.)There is no always-on penalty: MIP is always on. With 3 h/day at 50,000 lux the solar lens makes smartwatch mode effectively unlimited and stretches multiband GPS from 24 h to about 60 h.
Battery, Single-Band GPS ( h)41Sources conflict: 40 h (the5krunner spec sheet, 45 mm, no solar) vs 50 h (garminrumors spec wiki, lower bound of its 45/50 mm range)
Battery, Multiband GPS ( h)Not published by COROS for the 42 mm in any source reviewed here. For reference the 46 mm is rated 65 h all-systems vs 41 h dual-frequency — expect a similar ~35-40% drop.24
GNSS BandsDual-frequency L1+L5 chipset covering GPS, GLONASS, Galileo, BeiDou and QZSS. DC Rainmaker warns GPS accuracy degrades noticeably when route navigation is running.Multi-band dual-frequency L1+L5 (GPS, GLONASS, Galileo, BeiDou, QZSS) with SatIQ — DC Rainmaker confirms every Instinct 3 got multiband
Onboard MapsFree global offline topographic and landscape maps with street/trail names and POIs, downloaded through the COROS app, plus turn-by-turn on preloaded routes. No ClimbPro equivalent and no automatic rerouting.None. No offline maps and no route storage to speak of — DC Rainmaker called shipping a $400-plus outdoor watch without maps 'pretty hard to swallow'.
Music StorageMP3 files only, sideloaded. No streaming services and no phone-music control.None. No music storage, no streaming, no Wi-Fi — phone music control only.
Training Platform & SubscriptionCOROS app and EvoLab analytics are entirely free, no subscription tier. COROS' own metrics, not Firstbeat.Garmin Connect is free and every core training metric — Training Readiness, Training Load, Training Status, HRV Status, Body Battery, recovery time — is Firstbeat-derived and free on the watch (Garmin bought Firstbeat in 2020). Connect+ is $6.99/mo or $69.99/yr and adds only AI wellness prompts, 3D maps, Trails+ routing, extra badges and nutrition logging — nothing a training plan depends on.
External Sensor SupportBluetooth only — no ANT+ at all, which rules out ANT+-only power metersANT+ and Bluetooth chest straps, pods and power meters
Data ExportFree .FIT/GPX export plus auto-sync to Strava, TrainingPeaks, Apple Health and Health ConnectFull .FIT file access over USB/MTP plus free automatic sync to Strava, TrainingPeaks, Runalyze, intervals.icu and others through Garmin Connect.
Warranty24 months12 months
ColorsBlackBlack

Category Scores

GPS AccuracyTrace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.
COROS APEX 4 (42mm)
8.0
Garmin Instinct 3 Solar (45mm)
8.6
Battery HonestyHow much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.
COROS APEX 4 (42mm)
8.8
Garmin Instinct 3 Solar (45mm)
9.2
Training & RecoveryDepth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap.
COROS APEX 4 (42mm)
7.8
Garmin Instinct 3 Solar (45mm)
7.8
Navigation & MapsReal routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch.
COROS APEX 4 (42mm)
7.8
Garmin Instinct 3 Solar (45mm)
2.8
Heart RateOptical wrist accuracy during intervals and burst efforts, and whether the watch pairs with ANT+ and/or Bluetooth chest straps as a fix.
COROS APEX 4 (42mm)
7.4
Garmin Instinct 3 Solar (45mm)
7.2
DisplayBrightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.
COROS APEX 4 (42mm)
6.2
Garmin Instinct 3 Solar (45mm)
6.4
Build & ComfortCase materials, lens (sapphire vs glass), weight on the wrist and durability ratings.
COROS APEX 4 (42mm)
8.6
Garmin Instinct 3 Solar (45mm)
8.2
ValueWhat the watch delivers per dollar against everything else in the comparison at the moment of purchase.
COROS APEX 4 (42mm)
8.6
Garmin Instinct 3 Solar (45mm)
7.0
GPS AccuracyBattery HonestyTraining & RecoveryNavigation & MapsHeart RateDisplayBuild & ComfortValue
COROS APEX 4 (42mm) Garmin Instinct 3 Solar (45mm)

GPS Accuracy

The Garmin Instinct 3 Solar (45mm) leads clearly here, 8.6 against 8.0 — a 0.6-point margin on trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.. If that is what you are buying for, the COROS APEX 4 (42mm) does not close the gap elsewhere.

Battery Honesty

The Garmin Instinct 3 Solar (45mm) is marginally ahead, 9.2 to 8.8. A gap this small rarely decides a purchase on its own, though it counts if how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode. is your priority.

Training & Recovery

The COROS APEX 4 (42mm) and Garmin Instinct 3 Solar (45mm) are level here, at 7.8/10 each. depth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap. is not what separates these two — look to the categories where the scores diverge.

Heart Rate

The COROS APEX 4 (42mm) is marginally ahead, 7.4 to 7.2. A gap this small rarely decides a purchase on its own, though it counts if optical wrist accuracy during intervals and burst efforts, and whether the watch pairs with ANT+ and/or Bluetooth chest straps as a fix. is your priority.

Display

The Garmin Instinct 3 Solar (45mm) is marginally ahead, 6.4 to 6.2. A gap this small rarely decides a purchase on its own, though it counts if brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour. is your priority.

Build & Comfort

The COROS APEX 4 (42mm) is marginally ahead, 8.6 to 8.2. A gap this small rarely decides a purchase on its own, though it counts if case materials, lens (sapphire vs glass), weight on the wrist and durability ratings. is your priority.

Value

The COROS APEX 4 (42mm) leads clearly here, 8.6 against 7.0 — a 1.6-point margin on what the watch delivers per dollar against everything else in the comparison at the moment of purchase.. If that is what you are buying for, the Garmin Instinct 3 Solar (45mm) does not close the gap elsewhere.

Best For

Choose the COROS APEX 4 (42mm) if…

  • Navigation & Maps matters most to you — the COROS APEX 4 (42mm) scores 7.8/10 here (real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch.).
  • Value matters most to you — the COROS APEX 4 (42mm) scores 8.6/10 here (what the watch delivers per dollar against everything else in the comparison at the moment of purchase.).
  • Build & Comfort matters most to you — the COROS APEX 4 (42mm) scores 8.6/10 here (case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.).

Choose the Garmin Instinct 3 Solar (45mm) if…

  • GPS Accuracy matters most to you — the Garmin Instinct 3 Solar (45mm) scores 8.6/10 here (trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.).
  • Battery Honesty matters most to you — the Garmin Instinct 3 Solar (45mm) scores 9.2/10 here (how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.).
  • You want to spend less — it's $29 cheaper.

Pros & Cons

COROS APEX 4 (42mm)

Pros

  • +Free global offline topo maps with street and trail names at $429 — Garmin charges $749.99 before you get maps
  • +Titanium bezel and sapphire glass at a price where rivals use aluminium and Gorilla Glass
  • +MIP means the 41 h all-systems figure is what you get, with no always-on display tax
  • +Two years of warranty and zero subscriptions anywhere in the platform

Cons

  • COROS does not publish a dual-frequency battery figure for the 42 mm, and dual-frequency is where accuracy actually lives
  • DC Rainmaker measured a real GPS accuracy drop when a route is loaded and navigation is active
  • MIP display is dim indoors and at night compared with every AMOLED rival here
  • No ANT+, no NFC payments and no LED flashlight
  • The depth gauge has no certification and cannot record dives to the app, and there are no dive sport profiles

Garmin Instinct 3 Solar (45mm)

Pros

  • +MIP plus solar is the one combination here where the headline battery figure is close to what you actually get
  • +Multi-band L1+L5 GNSS at $399.99, in a 10 ATM, MIL-STD-810 tested case
  • +Solar can push smartwatch mode to effectively unlimited and multiband GPS from 24 h to about 60 h
  • +No always-on display penalty at all — the screen is transflective and permanently visible

Cons

  • No offline maps and no music storage, on a watch that costs as much as an Amazfit T-Rex 3 Pro that has both
  • Storage is the reason: sources conflict badly — the garminrumors wiki says 32 GB while DC Rainmaker and Tom's Guide report roughly 120-128 MB on Solar models, too small even to hold a firmware update alongside courses
  • Multiband drops runtime to 24 h without sun — a quarter of the 100 h Max Battery GPS headline
  • Older Elevate Gen 4 optical HR sensor, not the Gen 5 in cheaper Garmins
  • Monochrome 176x176 MIP screen looks a decade old next to every AMOLED rival, and there is no touchscreen

Shop by Need

FAQs

Is the COROS APEX 4 (42mm) or Garmin Instinct 3 Solar (45mm) better overall?+

Based on our 8-category scoring, the COROS APEX 4 (42mm) comes out ahead overall. See the full breakdown in the scores section above — the right pick still depends on which categories matter most for your use case.

Which is better for Navigation & Maps, the COROS APEX 4 (42mm) or the Garmin Instinct 3 Solar (45mm)?+

The COROS APEX 4 (42mm) scores higher on Navigation & Maps (7.8/10 vs 2.8/10) — real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch..

Which is better for Value, the COROS APEX 4 (42mm) or the Garmin Instinct 3 Solar (45mm)?+

The COROS APEX 4 (42mm) scores higher on Value (8.6/10 vs 7.0/10) — what the watch delivers per dollar against everything else in the comparison at the moment of purchase..

Which is better for GPS Accuracy, the COROS APEX 4 (42mm) or the Garmin Instinct 3 Solar (45mm)?+

The Garmin Instinct 3 Solar (45mm) scores higher on GPS Accuracy (8.6/10 vs 8.0/10) — trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world..

Which is better for Build & Comfort, the COROS APEX 4 (42mm) or the Garmin Instinct 3 Solar (45mm)?+

The COROS APEX 4 (42mm) scores higher on Build & Comfort (8.6/10 vs 8.2/10) — case materials, lens (sapphire vs glass), weight on the wrist and durability ratings..

Is the COROS APEX 4 (42mm) worth the price difference over the Garmin Instinct 3 Solar (45mm)?+

The Garmin Instinct 3 Solar (45mm) is the cheaper option at $399.99 versus $429. Whether the pricier model is "worth it" depends on how much you value its lead in Navigation & Maps.

What's the warranty on the COROS APEX 4 (42mm) vs the Garmin Instinct 3 Solar (45mm)?+

The COROS APEX 4 (42mm) ships with a 24-month warranty; the Garmin Instinct 3 Solar (45mm) ships with a 12-month warranty. Always confirm current terms on the manufacturer's site before buying.

Should I wait for the next model instead of buying either of these?+

If either model is more than two years old, a successor may be close — check the "Latest Model" link on each product page. Otherwise, both are current, well-supported options and there's no strong reason to wait.

Cheaper Option

Garmin Forerunner 170 (43mm) — $299.99

Premium Option

Suunto Race 2 (stainless steel) — $499.00

Specifications and prices for both products last verified . Scores are calculated from published specifications — see how we compare products.

You May Also Like