Casio G-Shock GA-B2100 — “Casio Oak” upgrade with Bluetooth and Solar Power

GA-B2100BNR-1A — Updated October 2022 color! Buy it on Amazon!

Rating: 5 out of 5.
Size★★★★★
Weight★★★★★
Functions★★★★★
Materials★★★★★
Price★★★★★

GA-B2100 Model Range *may be updated


Quick Content Guide

  1. GA-B2100 Model Range *in different colors and bands
  2. General information about the watch *year of first release, model range etc.
  3. G-Shock GA-B2100 Display Guide *for key functions only
  4. Enjoy Japanese Unique Features in GA-B2100! *key features of GA-B2100 series
  5. G-Shock GA-B2100 on the wrist *only images and only on the wrist
  6. GA-B2100 Usage Patterns *what the watch is usually meant for
  7. Other G-Shock GA Watches *similar by price and functions but different by cases
  8. Official GA-B2100 Specs *all details and for base version GST-B400-1A
  9. G-Shock GA-B2100 PROs & CONs *by experts with 10 years experience
  10. GA-B2100 Comparison Table *with similar G-Shock Watches
  11. Recent News about GA-B2100 *the latest breaking news and videos


General Information

Price$170
*average Amazon Price, we may earn commission from purchases
Year of first Release2022
Suitable for Wrist Size145 – 215 mm
Module Number5689 / Manual
Model RangeOctagon
Battery TypeSolar (G-Shock Batteries)
Other Divisions the GA-B2100 belongs to: *you may find all watches of the division by clicking on the linkG-Shock Ana-Digi
G-Shock Bluetooth
G-Shock Carbon Core Guard
G-Shock For Small Wrists
G-Shock Solar
G-Shock 2022

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Enjoy Japanese Unique Features in GA-B2100!

SIMPLICITY OF DESIGN

While maintaining the iconic octagonal form of the GA-2100 inherited from the very first G-SHOCK, the GA-B2100 now also has Smartphone Link and Tough Solar power capabilities. It also employs the Carbon Core Guard structure to preserve a similar fit on the wrist as the original model.

DIAL WITH ENCHANCED TEXTURE

The dual-layer dial construction highlights the dimensionality of the LCD and inset dial. Meticulous attention to detail gives the dial a look of enhanced texture, especially the different surface treatments we apply to the dial face and inset dial.

HOMAGE TO THE FIRST COLOR G-SHOCK MODELS

We have brought back the classic colors first used in the G-SHOCK 5600 line for the case and band, inspired by the concept of getting back home. The color scheme of the DW-5600C also includes accents to the dial. Blue, green, and all-black options offer clean, minimalist color choices.

CARBON CORE GUARD STRUCTURE

The shock-resistant structure unique to G-SHOCK protects the module, with a carbon fiber-reinforced resin case offering strength, lightness, and excellent weather resistance.

SOLAR POWER

Solar-powered timekeeping with Bluetooth® for enhanced accuracy and reliability

SUPER ILLUMINATOR

Super Illuminator (high-brightness double LED light) for maintaining watch readability in the dark

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G-Shock GA-B2100 Display Guide *for key functions only. For you to know how it works))

General Display

  1. Hour hand
  2. Minute hand
  3. Mode hand
    Indicates the current mode. In the Timekeeping mode, this hand shows the current charge level.
  4. LCD

Shifting Hands to Read the Digital Display

Hand shift moves the hands out of the way for easy viewing of display information.

Phone Finder

You can use phone finder to trigger a tone on the phone to make it easy to find. The tone is forced to sound even if the phone is in vibrate mode.

Checking World Time

Enter the World Time.
After the currently selected World Time City name appears, the watch will display the current time in that city.

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G-Shock GA-B2100 on the wrist!


GA-B2100 Usage Patterns *what the watch is usually meant for

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What we like in GA-B2100 *comments by experts with 10 years experience in writing about Casio watches
— Carbon Core Guard structure (protects the module by enclosing it in a carbon case. The case is made of fine resin embedded with carbon fibers for outstanding strength and crack resistance)
Tough Solar (CASIO’s original solar-charging system converts not only sunlight but also light from fluorescent lamps and other sources into power)
G-SHOCK Connected App (you may manage all watch settings through your phone)
— 200-meter water resistance (good for swimming but not for deep diving)

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Other G-Shock GA Watches *similar by price and functions but different by cases

These are not all G-Shock GA Series. Here is a list of All G-Shock GA Watches →


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Official Casio Description.

Upgrade the retro look you love with the octagonal GA-2100 line, which inherits the design concept of the very first G-SHOCK, but now with Smartphone Link and Tough Solar power.


Official GA-B2100 Specs / Features *for base version GA-B2100-1A

  • Case size: (L× W× H)48.5 × 45.4 × 11.9 mm
  • Weight: 52 g
  • Case / bezel material: Carbon / Resin 
  • Band: Resin
  • Construction:
    Shock Resistant
    Carbon Core Guard structure
  • Water resistance: 200-meter water resistance
  • Power supply and battery life: Tough Solar (Solar powered)
  • Smartphone Link feature: Mobile link (Wireless linking using Bluetooth®)
  • Apps: CASIO WATCHES
  • App connectivity feature:
    Auto time adjustment
    Easy watch setting
    Approximately 300 world time cities
    Time & place
    Reminder
    Phone finder
  • Glass: Mineral Glass
  • Other: Neobrite
  • World time: World time 38 time zones (38 cities + coordinated universal time), city code display, city name display, daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping
  • Stopwatch:
    1/100-second stopwatch
    Measuring capacity: 00’00”00~59’59”99 (for the first 60 minutes) 1:00’00~23:59’59 (after 60 minutes)
    Measuring unit: 1/100 second (for the first 60 minutes) 1 second (after 60 minutes)
    Measuring modes: Elapsed time, lap/split time
  • Timer: Countdown timer
    Measuring unit: 1 second
    Countdown range: 60 minutes
    Countdown start time setting range: 1 second to 60 minutes (1-second increments and 1-minute increments)
  • Alarm/hourly time signal:
    5 daily alarms
    Hourly time signal
  • Light: Double LED light LED light for the face (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow) LED backlight for the digital display (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)
  • Calendar: Full auto-calendar (to year 2099)
  • Mute feature: Button operation tone on/off
  • Energy saving feature: Power Saving (display goes blank to save power when the watch is left in the dark)
  • Battery display/alert: Battery level indicator
  • Run time: Approx. battery operating time: 7 months on rechargeable battery (operation period with normal use without exposure to light after charge) 18 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge)
  • Accuracy: ±15 seconds per month (with no mobile link function)
  • Other features:
    Hand shift feature (Hands move out of the way to provide an unobstructed view of digital display contents.)
    12/24-hour format
    Date/month display swapping
    Day display (days of the week selectable in six languages)
    Regular timekeeping: Analog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (battery level, mode) Digital: Hour, minute, second, pm, month, date, day

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G-SHOCK GA-B2100 PROs & CONs

*we composed all points based on our ten years experience in writing about CASIO watches. We know what matters when you are searching for your ideal G-SHOCK!

– Solar Powered (Tough Solar). No need to worry about the battery change
– Octagonal Form (trendy & stylish design). Luxury brands are also boasting an OAK design
– Bluetooth (easy to operate via smartphone)
– Bluetoot Accuracy Calibration (checks if the watch shows the ideal time)
– Carbon Core Guard (the watch is more lightweight but stronger in comparison with a traditional case)
– Affordable price
– Good hands readability
– Additional digital display enhances functionality
– Double LED Light (one for the face and one for the digital display)

– Only traditional functions (World time, Stopwatch, Timer, Alarms etc.)
– Without sports functions (like GPS, Steptrecker, advanced timers)
– No Radio Calibration (you have only Bluetooth Time Sync)
– Difficult digital display readability (if the model uses a negative display)
– Budget-friendly materials but durable
– No Second Hand

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GA-B2100 Comparison Table with similar G-Shock Watches


GA-B2100

GM-B2100

GA-2100

Price (Amazon)

Year of first Release

2022

2022

2019

Accuracy

Bluetooth (via phone app)

Bluetooth (via phone app)

±15 seconds per month

SmartWatch Features

Yes

Yes

No

Light

Double LED light (Super Illuminator)

Double LED light (Super Illuminator)

Neobrite (hands and hour markers) Double LED light

Alarm

5 daily alarms

5 daily alarms

5 daily alarms

Timer

Measuring unit: 1 second
Countdown range: 60 minutes
Countdown start time setting range: 1 second to 60 minutes (1-second increments and 1-minute increments)

Measuring unit: 1 second
Countdown range: 60 minutes
Countdown start time setting range: 1 second to 60 minutes (1-second increments and 1-minute increments)

Measuring unit: 1 second
Countdown range: 24 hours
Countdown start time setting range: 1 second to 24 hours (1-second increments, 1-minute increments and 1-hour increments)

Stopwatch

1/100-second stopwatch
Measuring capacity:
00'00''00~59'59''99 (for the first 60 minutes)
1:00'00~23:59'59 (after 60 minutes)
Measuring unit:
1/100 second (for the first 60 minutes)
1 second (after 60 minutes)
Measuring modes: Elapsed time, lap/split time

1/100-second stopwatch
Measuring capacity:
00'00''00~59'59''99 (for the first 60 minutes)
1:00'00~23:59'59 (after 60 minutes)
Measuring unit:
1/100 second (for the first 60 minutes)
1 second (after 60 minutes)
Measuring modes: Elapsed time, lap/split time

1/100-second stopwatch
Measuring capacity:
00'00''00~59'59''99 (for the first 60 minutes)
1:00'00''~23:59'59'' (after 60 minutes)
Measuring unit:
1/100 second (for the first 60 minutes)
1 second (after 60 minutes)
Measuring modes: Elapsed time, split time, 1st-2nd place times

Hourly Time Signal

Yes

Yes

Yes

World Time

38 time zones (38 cities + coordinated universal time), city code display, city name display, daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping

38 time zones (38 cities + coordinated universal time), city code display, city name display, daylight saving on/off, auto summer time (DST) switching, Home city/World time city swapping

31 time zones (48 cities + coordinated universal time), daylight saving on/off

Screw Back

No

Yes

No

Carbon Core Guard

Yes

No

Yes

Case / bezel material

Carbon / Resin

Stainless steel

Carbon / Resin

Glass

Mineral Glass

Mineral Glass

Mineral Glass

Battery

Solar powered (CTL920)

Solar powered (CTL920)

3 years on SR726W

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

48.5×45.4×11.9

49.8×44.4×12.8

48.5×45.4×11.8

Full features (if you want to know more)

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Recent News about GA-B2100 

All G-SHOCK GA-B2100 News →

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Not sure about GA-B2100? There are more G-Shocks!

Back to All G-Shock Models →