Casio G-Shock GA-2100 (CasiOak) vs GD-100
Buy the GA-2100 for a slimmer, lighter watch that fits under a shirt cuff and adds Bluetooth time sync. Buy the GD-100 for the biggest, easiest-to-read digits and the longest battery life. As of November 3, 2026, the GA-2100 is $95.00 at eBay and the GD-100 is $70.98 at Amazon, so the GD-100 is about $24 cheaper.
Today the GD-100 costs $24.02 less at its best price.
Ask our shopping agent
Casio G-Shock GA-2100 (CasiOak)
4.3Choose the GA-2100 if you want a slim 11.8 mm case, an analog-digital dial and Bluetooth time setting in a watch that still takes 200 m of water.
- Slim 11.8 mm case slides under a cuff
- Bluetooth keeps time accurate and handles time zones
- Analog hands with a night light for dark reading
- 200 m water resistance and shock-resistant resin build
What separates them
| Casio G-Shock GA-2100 (CasiOak) | GD-100 | |
|---|---|---|
| Case size and thickness | 45 mm wide, 11.8 mm thick | 55.0 x 51.2 x 17.4 mm |
| Weight | About 51 g | 72 g |
| Display | Analog hands plus a small digital window | Full digital LCD with large digits |
| Connectivity | Bluetooth for automatic time setting and time-zone changes | None; set by buttons |
| Battery | About 3 years on SR726W cells | About 7 years on one CR2025 |
| Alarms | Daily alarm plus hourly time signal | 5 daily alarms |
| Water resistance | 200 m (20 ATM) | 200 m (20 ATM) |
| Price, November 3, 2026 |
Price history
- Casio G-Shock GA-2100 (CasiOak): lowest $65.00 on Oct 29; $104.94 on Nov 4.
- GD-100: lowest $70.98 on Nov 4 at Amazon.
Prices at every store
Casio G-Shock GA-2100 (CasiOak)
- Macy'sNew
In stock
$110.00Free shippingObserved at 10:42 PM - eBayPre-owned
Availability unknownSold by chronoshadeoutlet (99.7% positive, 2,600 ratings)Returns: Set by the eBay seller; the eBay Money Back Guarantee covers an item that doesn't arrive or isn't as described.
$89.99Free shippingVerified - eBayNew
Availability unknownSold by chronoshadeoutlet (99.7% positive, 2,600 ratings)Returns: Set by the eBay seller; the eBay Money Back Guarantee covers an item that doesn't arrive or isn't as described.
$95.00Free shippingVerified - AmazonNew
Availability unknown
As an Amazon Associate, Deal.ai earns from qualifying purchases.
$104.94Free shippingObserved at 10:42 PM
Also available at
- BuckleCheck price at Buckle
- NordstromCheck price at Nordstrom
- WalmartCheck price at Walmart
Specs compared
| Spec | Casio G-Shock GA-2100 (CasiOak) | GD-100 |
|---|---|---|
| Water Resistance | 200 m (20 ATM) | 200 Metres Water Resistant |
| Band Material | Resin | Resin |
| Model | Casio G-Shock GA-2100-1A1 Price: ~– ASIN: B0DSW… | Casio G-Shock GD-100-1BCR Price: ~– ASIN: B003U… |
| Bezel Color | Gray | — |
| Closure | Buckle | — |
| Dial Pattern | Solid | — |
| Number Of Jewels | 0 Jewels | — |
| Indices | Baton Indexes | — |
| Year Manufactured | 2020-Now | — |
| Band / Strap | Two-Piece Strap | — |
What reviewers say
Casio G-Shock GA-2100 (CasiOak)
Owners widely praise the CasiOak as a tough, good-looking daily watch that punches far above its price. The common complaints are the size on slim wrists and the plastic feel of the case and strap.
- Toughness and shock resistance for the money
- Slim profile compared with other G-Shocks
- Octagonal design that looks more expensive than it is
- Legible analog-digital dial
- Large 45 mm case on smaller wrists
- Resin strap can feel stiff and plasticky
- No solar or Bluetooth on the base model
GD-100
Owners rate it highly, 4.6 out of 5 from 142 ratings, and most praise the size, readability and toughness for the money. Complaints tend to focus on bulk and the plain resin strap rather than the watch itself.
Questions and answers
- Which is better for small wrists?
- The GA-2100. Its 45 mm case and 11.8 mm thickness sit much flatter than the GD-100's 55 mm case and 17.4 mm depth.
- Which has the longer battery life?
- The GD-100, at about 7 years on a CR2025. The GA-2100 runs about 3 years on SR726W cells.
- Is the GA-2100 worth the extra money?
- At $95.00 at eBay versus $70.98 at Amazon, you pay about $24 more for the slimmer case, analog hands and Bluetooth time sync. Skip it if you mainly want big digits and long battery life.
- Which is easier to read in the dark?
- The GA-2100 has a light that illuminates the hands and digital screen. The GD-100 uses an LED backlight on its full LCD, which lights the whole face.
- Do both handle swimming?
- Yes. Both are rated 200 m (20 ATM), which covers swimming and snorkeling but not scuba diving.
- Which has more alarms?
- The GD-100, with 5 daily alarms. The GA-2100 has a daily alarm and an hourly time signal.
More comparisons
- Casio G-Shock GA-2100 (CasiOak) vs Casio G-Shock DW-5600
- Casio G-Shock GA-2100 (CasiOak) vs G-Shock GW-M5610
- Citizen Eco-Drive Chandler vs Casio G-Shock GA-2100 (CasiOak)
- Tissot PRX Quartz vs Casio G-Shock GA-2100 (CasiOak)
- Casio G-Shock GA-2100 (CasiOak) vs CHANEL J12 BLEU X-RAY
- Casio G-Shock GA-2100 (CasiOak) vs G-Shock GMW-B5000
- Casio G-Shock DW-5600 vs GD-100