An ABC watch has an altimeter, a barometer and a compass, the three sensors that tell you how high you are, what the weather is about to do, and which way is north, without a phone signal. The category was defined by the G-Shock Rangeman and it is still the one to buy. This guide covers what each sensor does, the Rangeman we stock, and the watches to consider if you only need one of the three.
The three sensors
Altimeter: elevation from barometric pressure, calibrated at a known altitude, useful for tracking a climb. Barometer: pressure trend, which is a weather forecast; a fast drop means a storm. Compass: bearing, with a declination setting, for orienting a map.
G-Shock Rangeman GW9400-1B, $329.99
The reference ABC watch: triple sensor, a metal-guarded sensor button that works with gloves, sensor recall, three alert volumes, and G-Shock toughness in a blackout display. Rangeman.
If you only need tides
The G-Shock GBX100 shows tide graphs and sunrise for a chosen surf spot.
If you need to read it at night without sensors
A tritium Luminox Atacama field watch glows for 25 years and needs no button. No sensors.
If you want the look at $149
The Dango Spec-Ops has a compass-style dial and a Cerakote head, and no sensors. It is a watch, not an instrument.
Do you need one
If you hike above treeline, hunt, ski the backcountry or sail, a barometer on the wrist earns its place. If you do not, buy the watch you like.
Frequently asked questions
What is an ABC watch?
A watch with an altimeter, barometer and compass.
What is the best ABC watch?
The G-Shock Rangeman GW9400.
Does a smartwatch replace an ABC watch?
For a day, yes. For a week without charging, no.
How accurate is a watch altimeter?
Within tens of feet if calibrated at a known elevation and recalibrated as pressure changes.
Does the Rangeman have GPS?
The GW9400 has the triple sensor, not GPS.
The bottom line
The G-Shock Rangeman is the ABC watch. Everything else is a compromise in one direction.
Related reading
G-Shock Rangeman GW9400 review
Best G-Shock for EDC
Best tactical watches for 2026
