A popular digital series with advanced features. The large case and powerful bezel screws emphasize the visual power of the GW-7900 – the watch module is protected from any negative influences. The main advantage of the model is the availability of solar power [recharging the battery from daylight] and radio time synchronization. Surfers and people associated with the maritime business will find useful functions for themselves – the phase of the moon and the level of the ebb / flow in a particular place are displayed. Thanks to the electronic dial, the information is displayed in a detailed form. In addition to specific functions, the watch also has basic features – a 24-hour stopwatch, a timer, world clock, a calendar and backlight with automatic response when you turn your hand.
- Price — 90$ *average Amazon Price, we may earn commission from purchases
- Year of first Release — 2009
- Module Number — 3200 / Manual
- Model Range — STANDART DIGITAL (This Line includes Digital G-Shocks that are the best in “price/quality” category. Usually have traditional digital functions.)
- Other Divisions the GW-7900 belongs to: *you may find all watches of the division by clicking on the link
- Battery Type — Solar (G-Shock Batteries)
Feedback from Users *accumulated information from our own comments and emails, forum threads, socials, reviews, etc.
+ moon phase data
+ solar charging
+ easy to read
+ easy setup
+ automatic atomic calibration
+ larger display
– negative display
– small moongraph
Feedback from Experts *based on comparison info with similar watches by price, model range, etc.
+ very accurate. Radio-controlled (via atomic watch signals)
+ Full-Auto Illuminator
+ solar powered
+ Moon Graph
+ Tide Graph
– no Hourly Time Signal
– no Data Memory
GW-7900 Model Range *may be updated
The most distinctive specs of GW-7900 *Editorial
— 200-meter water resistance (good for swimming but not for deep diving)
— Tough Solar (CASIO’s original solar-charging system converts not only sunlight but also light from fluorescent lamps and other sources into power)
— Radio-controlled Watch; Multi band 6 (additional way for time sync. This watch receives time calibration radio signals that keep the displayed time accurate)
— Moon data (moon age of the specific date)
— Tide graph (tide level for specific date and time)
Official GW-7900 Video
Official Marketing Focus from Casio
The G-SHOCK G-Rescue series combine tough, high-performance digital timekeeping with radio-controlled accuracy. Large buttons are designed to allow operation while wearing thick gloves, for even those with protective clothing. Tide Graph and Moon Phase features show tide and moon information for preset areas. Other advanced features include highly shock-resistant construction, a Tough Solar power system, MULTIBAND 6 reception of six time calibration signals around the globe, and much more.
Official GW-7900 Specs / Features *for base version GW-7900B-1
- Full-Auto Illuminator
Automatically deactivates the Auto EL backlight function when surrounding light is sufficient, and activates it under dim light or dark conditions.
Shock-resistant construction protects against impact and vibration.
- Solar Power
A solar cell provides power for operation.
- Radio signal reception (EU, USA, Japan, China)
Whether in Europe, North America and Japan or in the outer reaches of Canada, Central America and China – once the watch has been set to the local time, it receives the relevant signal and shows the correct time wherever you are. In many countries, it also sets itself automatically to summer and winter time.
- Moon Phase Indicator
The moon phase indicator shows the current moon phase based to the earth
- Tide indicator
Once the high tide time has been entered for a selected location, the watch can display the low and high tide phases at this location on any given date. This can be quite useful, for example, if you want to know the patterns of the tides at your destination in advance.
- World time function
Displays the current time in major cities and specific areas around the world.
- Stopwatch function – 1/100 sec. – 24 hours
Elapsed time, split time and final time are measured with 1/100-sec accuracy. The watch can measure times of up to 24 hours.
- Timer – 1/1 min. – 24 hours
For fans of precision: the countdown timers help you to remember specific or recurring events by giving off an audible signal at a preset time. The time can be set to the nearest minute and up to 24 hours in advance. Ideal for people who need to take medicines every day or those who do interval training.
- 5 daily alarms
The daily alarm reminds you about recurring events with an acoustic signal at the time you have set. This model has 5 independent alarms for flexible reminders of important appointments.
- Snooze feature
Each time you stop the alarm, it sounds again after a few minutes.
- Button tones on/off
The button tones for using the mode button can be turned off. This means that the watch no longer beeps when switching from one function to another. Preset alarm or countdown timers remain active when the button tones are deactivated.
- Automatic calendar with Date, Day and Month
Once set, the automatic calendar always displays the correct date.
- 12/24-hour timekeeping
Times can be displayed in either a 12-hour or 24-hour format.
- Mineral glass
The tough mineral glass resists scratching.
- Resin case
- Resin band
Synthetic resin is the ideal material for wrist straps thanks to its extremely durable and flexible properties.
- Battery level indicator
An indicator shows the current battery level.
- Water resistance classification (20 bar)
Perfect for free diving without scuba gear: the watch is water resistant up to 20 bar according to ISO 22810.
- Dimensions (H x W x D)
52,40mm x 50,00mm x 17,70mm
approx. 71,00 g
GW-7900 Comparison Table with similar G-Shock Watches
Year of first Release
±15 seconds per month
Radio-controlled (via atomic watch signals)
±15 seconds per month
5 alarms (daily or one-time)
5 daily alarms
5 independent multi alarms
Measuring unit: 1/10 second
1/1 min. – 24 hours
Input range: 1 minute to 24 hours
Stopwatch function – 1/100 sec. – 24 hours
Hourly Time Signal
31 time zones (48 cities + coordinated universal time), daylight saving on/off, Home city / World time city swapping
Displays the current time in major cities and specific areas around the world
29 time zones (27 cities), city code display, daylight saving on/off
Case / bezel material
Resin / Stainless steel
7 years on CR2025
Solar Powered CTL1616
10 years on CR2025
Size (mm) *we consider 48.9×42.8×13.4 to be a traditional watch size (as in DW-5600). So you are to compare how far or close the watch is to this size
Full features (if you want to know more)
GW-7900 Replacement Band (Strap) *availability
We think it is very important (before buying a new watch) to know if there will be some choice as for replacement bands for GW-7900 (in future or even now). So we made a research and you shouldn’t worry about your future as the bands are available for buying.
Recent News about GW-7900
- [G-Shock Old Alternative] DW-8600 started in 1996 and how’s it going now?
- [G-Shock Comparison] GD-100 VS GW-7900 VS G-2900
- [Casio on TV] Eminem is wearing G-Shock GW-7900B-1
- [Live Photos] G-Shock STAR WARS – THE FORCE UNLEASHED GW-7900 & DW-6900
You ask, we answer…
CASIO’s original solar-charging system converts not only sunlight but also light from fluorescent lamps and other sources into power.
This is additional way for time sync. This watch receives time calibration radio signals that keep the displayed time accurate.
It means tide level for specific date and time.