Garmin · Instinct 3 Solar · 45mm
The tool watch, rebuilt as electronics.
A 45mm GPS watch in fibre-reinforced polymer with a metal-reinforced bezel, a built-in LED flashlight, a solar-charging display and a 10 ATM rating. It weighs 53 grams and is built to MIL-STD-810.
Charge & run
Garmin product page
DC Rainmaker review
The GPS Store listing
The GPS Store listing
Garmin product page
Garmin product page
Solar on a smartwatch
Every other watch in this site’s solar group uses light to replace a battery change. The Instinct 3 Solar uses it to stretch the time between charges. A solar layer over the always-on monochrome display tops up the cell whenever the watch is outdoors, which is where a GPS watch spends its time.
Garmin does not publish a single days-of-battery figure that we could confirm for this exact model, so we do not print one. The claim that holds is the simple one: the solar version runs longer than the non-solar Instinct 3 under the same use.
Built to MIL-STD-810
MIL-STD-810 is a US military test standard for thermal, shock and water resistance. Garmin states the Instinct 3 is built to it. The case is fibre-reinforced polymer, the bezel is metal-reinforced with visible corner screws, and the lens is chemically strengthened glass.
The water rating is 10 ATM, or 100m, which covers swimming and snorkelling. It is a fitness watch, not a dive computer. Five physical buttons around the case run everything, so it works with wet hands and gloves in a way a touchscreen does not.
What it is not
It is not a watch in the mechanical sense. There are no hands, no crown and no movement to admire. It is a GPS receiver, a compass, an LED flashlight and a set of sport-tracking tools in a 53-gram case, and it expects a phone app on the other end.
That is the trade. If you want the tool-watch idea, the G-Shock pages on this site are the analogue and digital versions of it. If you want the tool-watch idea plus a map of where you went, this is the one. All figures here come from Garmin and the sources listed, not from testing a unit ourselves.
Specs
- Reference
- Instinct 3 Solar 45mm
- Case size
- 45mm
- Movement
- GPS Smartwatch (Solar Charging)
- Caliber type
- Solar-Charging GPS Smartwatch
- Complications
- GPS, LED Flashlight
Specifications as published by Garmin. We research from manufacturer documentation and published sources rather than hands-on testing. Researched 2026-09-03.
Verdict
A rugged, solar-assisted GPS watch with a flashlight and a 100m rating, for people who want their tool watch to record the trail.
Strengths
- Solar charging extends time between charges
- MIL-STD-810 build, metal-reinforced bezel, strengthened glass
- Built-in LED flashlight, GPS and compass
- 53g and 10 ATM, so it can go swimming
Trade-offs
- Needs charging and a companion phone app
- Monochrome display, no analogue face
- 14.9mm thick with a chunky bezel
- No confirmed manufacturer battery-life figure to quote
Buy it if
Hikers, runners and anyone who wants GPS tracking and a torch on the wrist without babying the watch.
Skip it if
You want a mechanical or purely analogue watch, or you do not want another device to charge.
FAQ
No. It has an always-on monochrome digital display. The solar layer sits over that display and charges the battery in daylight.
Sources
- Garmin Instinct 3 Solar, Garmin product page
- Garmin Instinct 3 in-depth review, DC Rainmaker
- Garmin Instinct 3 Solar 45mm, The GPS Store listing
Researched and last updated 2026-09-03. We do not test watches in hand; every figure above is traceable to the manufacturer or the sources listed here.
Garmin Instinct 3 Solar 45mm
Reference Instinct 3 Solar 45mm
Prices and availability change; the band above is a research figure, so check the current listing.
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