Casio G-Shock GMA-S2100 — Octagonal Bezel for Girls

GMA-S2100P-4A — August 2023 Update

GMA-S2100 Model Range *may be updated

Quick Content Guide

  1. GMA-S2100 Model Range *in different colors and bands
  2. General information about the watch *year of first release, model range etc.
  3. Official GMA-S2100 Video *only from Casio Company
  4. G-Shock GMA-S2100 Display Guide *for key functions only
  5. G-Shock GMA-S2100 on the wrist! *only images and only on the wrist
  6. GMA-S2100 Usage Patterns *what the watch is usually meant for
  7. Feedback from Users and Experts *anonymous from different sources
  8. The most distinctive specs *from our Editorial point of view
  9. Other G-Shock GMA Watches *similar by price and functions but different by cases
  10. Official GMA-S2100 Specs *all details and for base version GMA-S2100-7A
  11. G-Shock GMA-S2100 PROs & CONs *by experts with 10 years experience
  12. GMA-S2100 Comparison Table *with similar G-Shock Watches
  13. Japanese Unique Features in GMA-S2100! *the most distinctive features in details
  14. Recent News about GMA-S2100 *the latest breaking news and videos

About the Watch in short. G-SHOCK is a synonym for toughness, state-of-the-art technology and perfect design. CASIO G-SHOCK watches guarantee maximum precision under the most extreme conditions.


March, 2021


110$ on Amazon →
This downsized version of the popular GA-2100 model has a simple, thin design that eliminates waste while maintaining a tough structure.
More →

February, 2020


130$ on Amazon →
The new dual-layer molded bezel cover of the GA-2110 model create great looking new designs.
More →

August, 2019


130$ on Amazon →
The new Analog-Digital combination model that inherits the form of original G-SHOCK
The octagon form that was also employed for the original DW-5000C is installed in the series with carbon core guard structure which is the 3rd evolution of the materials of G-SHOCK.
More →

See the full story here →

Return to the Content Guide ↑

General Information

*average Amazon Price, we may earn commission from purchases
Year of first Release2021
Suitable for Wrist Size145 – 200 mm
Module Number5611 / Manual
Model RangeG-SHOCK WOMEN (The Line includes watches that are smaller than original men’s variant, but have the same functions, technologies and other specs. Usually meant for women but also good for children and small wrists.)
Battery TypeSR726W x 2 (G-Shock Batteries)
Buy Battery on Amazon →
Other Divisions the GMA-S2100 belongs to: *you may find all watches of the division by clicking on the linkG-Shock Ana-Digi
G-Shock Carbon Core Guard
G-Shock 2021

Return to the Content Guide ↑

Official G-Shock GMA-S2100 Video

Return to the Content Guide ↑

G-Shock GMA-S2100 Display Guide *for key functions only. For you to know how it works))


Use the Timekeeping Mode to set and view the current time and date.
– To view the Home City name (English), press A.

Checking the Current Time in a Different Time Zone

You can use the World Time Mode to view the current time in one of 31 time zones (48 cities) around the globe. The city that is currently selected in the World Time Mode is called the “World Time City”.

Stopwatch Mode

The stopwatch measures elapsed time, split times, and two finishes.
– The stopwatch measures elapsed time in units of 1/100 seconds for the first hour, and in 1-second units after that for up to 24 hours total. After that, elapsed time reverts to zero and then stops.

Countdown Timer

The countdown timer start time can be set in 1-second increments up to a maximum of 24 hours. An alarm sounds when the countdown reaches zero.

Return to the Content Guide ↑

G-Shock GMA-S2100 on the wrist!

Return to the Content Guide ↑

GMA-S2100 Usage Patterns *what the watch is usually meant for

Return to the Content Guide ↑

Feedback from Users *accumulated information from our own comments and emails, forum threads, socials, reviews, etc.

+ love how the watch looks
+ cool and pretty for girls
+ the matte black looks incredible
+ the pink one is super stellar and sleek
+ the dials pop and it’s perfect for any summer outing

– too few colorways

Feedback from Experts *based on comparison info with similar watches by price, model range, etc.

+ timer
+ double LED light
+ World Time
+ 3 years battery
+ carbon reinforced resin case
+ 5 time alarms

– expensive but worth the money
– no Hourly Time Signal
– no Auto-Back Light

Return to the Content Guide ↑

What we like in GMA-S2100 *comments by experts with 10 years experience in writing about Casio watches
Compact size (46.2 x 42.9 x 11.2 mm, which is less than original GA-2100. Will suit perfectly on small wrists)
The first Octagon for Women (very popular style)
Good for children (boys and girls as the size fits and there is no any “Baby-G” name, that boys do not like)
Basic but useful functions (world time, 1/100-second stopwatch (24 hours), countdown timer, 5 alarms, hand shift function, etc)
Amazing colors line (color schemes aimed at women)

Return to the Content Guide ↑

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

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

Return to the Content Guide ↑

Official GMA-S2100 Specs / Features *for base version GMA-S2100-7A

  • Case / bezel material: Carbon reinforced resin / stainless steel
  • Resin Band
  • Shock Resistant
  • Mineral glass
  • 200-meter water resistance
  • Double illuminator and Neo display
  • World time function
  • Stop function – 1/100 sec. – 24 hours
  • Timer – 1/1 sec. – 24 hours
  • Automatic calendar with date, month and day of the week
  • 5 daily alarms
  • Hand moving function
  • 12/24 hour format
  • Pin buckle
  • +/- 15 sec accuracy (per month)
  • Approx. battery operating time: 3 years
  • Size of case : 46.2 mm x 42.9 mm x 11.2 mm
  • Total weight : 41g

Return to the Content Guide ↑


*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!

– Compact Design (46.2 × 42.9 × 11.2 mm while average watch size is 48.9 × 42.8 × 13.4 mm)
– Octagonal Form (trendy & stylish design). Luxury brands are also boasting an OAK design
– Carbon Core Guard (the watch is more lightweight but stronger in comparison with a traditional structure)
– Double LED Light (one for the face and one for the digital display)
– Good hands readability

– 3 years battery life
– No Tough Solar (no Solar Power)
– No Second Hand
– Poor digital display readability (if the model uses negative display type)
– Budget-friendly materials

Return to the Content Guide ↑

GMA-S2100 Comparison Table with similar G-Shock Watches


Price (Amazon)

Year of first Release




±15 seconds per month

±15 seconds per month

 ±15 seconds per month

SmartWatch Features





Double LED light: LED light for dial, LED backlight for LCD

Electro-luminescent backlight

LED light
Auto light switch, selectable illumination duration, afterglow


5 time alarms

Multi-function alarm

5 daily alarms (with 1 snooze alarm)


Set unit: 1 second, maximum set: 24 hours, measured in 1 second units

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)
Other: Auto-repeat

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


(1/100 second (less than 1 hour) / 1 second (1 hour or more), 24-hour counter, with split)

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

1/1000-second stopwatch
Measuring capacity: 99:59’59.999”
Measuring modes: Elapsed time, lap time, split time
Others: Speed (0 to 1998 units/hour), Distance input (0.0 to 99.9)
Mach indicator (speed exceeding 1225 units/hour)

Hourly Time Signal




World Time




Auto-Back Light




Data Memory




Moon Graph




Tide Graph




Case / bezel material

Carbon reinforced resin / stainless steel

Resin / Stainless steel



Mineral Glass

Mineral Glass

Mineral Glass


3 years on SR726W

2 years on CR1616

2 years on CR1220

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)

Return to the Content Guide ↑

Enjoy Japanese Unique Features in GMA-S2100!

*some images are about G-Shock 5000/5600 cases, but the technology, approaches, concepts and philosophy remains the same for the whole G-Shock Model Range

Hollow case structure. Based on a realization that “shocks are not transmitted inside a bouncing rubber ball,” the structure was designed to let the module float inside the case, relieving shocks transmitted from outside. Today, the module’s shock resistance is realized through further technical innovations. But the revolutionary tough structure that gave G-SHOCK its origin began here.

All-directional covering. If the watch is dropped, the protruding bezel fully enclosing it absorbs the shock, protecting the buttons directly connected to the module and alleviating shocks from all directions. The bezel also guards the surface of the crystal. The band is curved stiffly at the point of connection with the case, moreover, enabling it to serve as a shock absorber and prevent direct shocks to the back of the case.

Protective cushioning of key parts. The crystal oscillator and other critical parts inside the module are guarded individually by cushioning material. Any strong shock to the watch causes immediate distortion of the cushioning inside the module, preventing contact failure and malfunction.

Japan Quality. Constructed with genuine quality, CASIO products provide truly practicable applications in which functionality and beauty combine. The leading-edge LSI technologies and skilled craftsmanship that give life to CASIO watches exemplify the quality Japan boasts in the world marketplace.
For CASIO, “faith in manufacturing” refers to an inexorable advancement of digital technologies and an uncompromising commitment to fine craftsmanship. This faith engenders unparalleled performance that not only elevates CASIO watches as close as possible to perfection, but that actually changes their wearers’ lifestyles.

Recent News about GMA-S2100 

All G-SHOCK GMA-S2100 News →

Return to the Content Guide ↑

Not sure about GMA-S2100? There are more G-Shocks!

Back to All G-Shock Models →

0 0 votes
Article Rating
Notify of

Inline Feedbacks
View all comments