Casio G-Shock · Manufacturer image, authorised for editorial use
G-Shock · Analog-Digital
G-Shock GA-2100
GA-2100-1A1
The octagonal G-Shock that made the line wearable with a jacket: 11.8 mm, carbon-reinforced resin and 200 m of shock-proof water resistance.
Street price
$99
88
Selection Score
88 out of 100
Provisional
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At a Glance
- Quartz movement — ±15 seconds per month (casio specification)
- Chronograph sub-dials
- Digital display with backlight
- 200 m water resistance
- Mineral crystal
- Luminous hands and markers
Specifications
- Brand
- G-Shock
- Collection
- Analog-Digital
- Movement
- Casio module 5611, caliber 5611, battery, approximately 3 years of power reserve, rated ±15 seconds per month (casio specification)
- Case
- Carbon Core Guard resin, 45.4 mm diameter, 11.8 mm thick, 48 mm lug-to-lug
- Crystal
- Mineral
- Bracelet / strap
- Integrated resin strap, Pin buckle, Integrated
- Water resistance
- 200 m (656 ft)
- Dial colours
- Black
- Style
- Sport, Everyday, Digital
- Recommended wrist
- Small, Medium, Large
- Country of origin
- Japan
What we like
- 11.8 mm — by far the slimmest G-Shock case
- Carbon Core Guard construction with 200 m water resistance
- 51 g, light enough to sleep in
- Analog hands plus a digital display without visual clutter
Full specifications
- Brand
- G-Shock
- Model
- GA-2100
- Reference
- GA-2100-1A1
- Collection
- Analog-Digital
- Street price
- $99
- MSRP
- $99
- Movement type
- Quartz
- Movement
- Casio module 5611
- Caliber
- 5611
- Power reserve
- Battery, approximately 3 years
- Stated accuracy
- ±15 seconds per month (Casio specification)
- Balance spring
- Not published
- Case diameter
- 45.4 mm
- Case thickness
- 11.8 mm
- Lug-to-lug
- 48 mm
- Lug width
- Integrated
- Weight
- 51 g
- Case material
- Carbon Core Guard resin
- Crystal
- Mineral
- Water resistance
- 200 m (656 ft)
- Dial colours
- Black
- Bracelet / strap
- Integrated resin strap
- Bracelet material
- Resin
- Clasp
- Pin buckle
- Date
- No
- GMT
- No
- Chronograph
- Yes
- Style
- Sport · Everyday · Digital
- Recommended wrist
- Small · Medium · Large
- Country of origin
- Japan
- Released
- 2019
- Selection Score
- 88 / 100
Score Breakdown
RatingWeightPoints
- 25%24.0
Value
- 20%14.0
Movement
- 15%13.8
Build Quality
- 15%13.5
Design
- 10%9.4
Wearability
- 10%8.5
Features
- 5%4.5
Brand & Ownership
Selection Score88
Seven pillars, each rated 0–10 and weighted as shown. The total is the sum of the weighted ratings — the headline number can never disagree with its own breakdown.
Ratings are demo data pending editorial review.
Where to Buy
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G-Shock US
$99 · Price checked August 1, 2026
Watch Brands: G-Shock
G-Shock is Casio's shock-resistance programme, launched in 1983 around a single requirement: survive a ten-metre drop. Four decades later it remains the reference for durability at any price.
