Disclosure: This article contains affiliate links, marked with *. If you make a purchase through one of these links, I may earn a commission. There is no additional cost to you. As an Amazon Associate, I earn from qualifying purchases.
The Casio G-Shock GA-2100 was released back in 2019 and within just a few years became a true phenomenon in the watch world. In 2026, I finally managed to get one for myself.
For several months now, the GA-2100, better known as ‘CasiOak’, has accompanied me through my rather unspectacular everyday life..
Between parcel delivery, lab work and gym, I’ve been able to get a pretty good idea of her strengths and weaknesses.
‘CasiOak’ – Why is it called that?
Good question. For casual watch wearers, this term is initially just a youth slang word on the internet. In fact, this nickname is based on the similarity of its octagonal bezel to the Audemars Piguet Royal Oak. And that brings us to an interesting fact:
A Casio GA-2100 costs around 100 euros, depending on the model. Easily affordable for the average person. An Audemars Piguet Royal Oak, however, starts at 30,000 euros and goes up from there. That’s 300-times more than a standard GA-2100.
But the CasiOak isn’t just a cheap imitation. You get a stylish watch with the typical G-Shock shock resistance, 20 bar water resistance, and excellent everyday usability. These qualities of a Casio G-Shock, combined with its distinctive design and very attractive price, have made this watch a perennial favorite and bestseller in recent years..
Since its initial release seven years ago, the GA-2100 family has grown considerably. Those who prefer a sleek stainless steel case to resin can opt for the metal version: Read my detailed review here. Review of the Casio G-Shock GM-2100.
The most important variants of the GA-2100
| Variante | Erscheinung | Material | Solar | Bluetooth | Besonderheit |
|---|---|---|---|---|---|
| GA-2100 | Basis-Modell (2019) | Resin / Carbon Core Guard | Nein | Nein | Die originale CasiOak mit analog-digitalem Display |
| GA-B2100 | Weiterentwicklung | Resin / Carbon Core Guard | Ja | Ja | Solar und Smartphone-Link |
| GM-2100 | Metall-Variante | Edelstahl-Lünette + Resin | Nein | Nein | Hochwertigerer Look bei ähnlicher Technik |
| GBM-2100 | Premium-Modell | Edelstahl-Lünette | Ja | Ja | Metalloptik mit moderner Technik |
| GMB-2100 | Full Metal | Edelstahlgehäuse & Stahlband | Ja | Ja | Vollständige Metall-CasiOak |
| MRG-B2100 | Luxus-Modell | Titan und High-End-Materialien | Ja | Ja | Spitzenmodell der 2100-Serie |
| GMA-S2100 / GM-S2100 | Kompakte Versionen | Resin bzw. Metall | Modellabhängig | Modellabhängig | Kleinere Gehäuse für schmalere Handgelenke |
Practical experience in everyday life
My daily routine consists of: lugging packages at a parcel service, working in a biotechnological lab, and, because it’s expected… the gym. There, you bump into steel beams, wear a lab coat all day, have to time experiments, and finally, you pump heavy weights and, of course, do cardio… Admittedly, not everyone commutes between a parcel center, a lab, and a gym every day. But that’s precisely why I was able to test the watch under such diverse conditions. That’s why I spared no expense in finding out what general questions you all have. Let’s get started!
- Does the GA-2100 also fit narrow wrists? Yes. With a wrist circumference of 17.5 cm, I initially had my doubts. But the watch actually fits surprisingly well. In contrast to other bulky G-Shocks, its 11.8 mm thickness makes it appear rather delicate, despite a case diameter of around 45 millimeters.
- Long-term wearing comfort: Weighing around 51 grams, it’s barely noticeable. Even after a long day in the lab wearing a lab coat.
- Readability: The analog hands are usually easy to read. In everyday use, I had no problems with them in daylight, whether in the lab, during sports, or on the go. However, it becomes more difficult at night with a black dial. Although the hands are luminescent and Casio also includes an LED backlight, models with a negative display remain the biggest weakness of the GA-2100. Those who choose a lighter color variant will encounter this problem much less frequently. I explain in detail why positive, negative, and modern MIP displays differ considerably in G-Shock watches in my Guide to the display readability of G-Shock watches
- Resin-Armband: For me, this is simply the biggest weakness. While the bracelet is robust and resistant to rain and sweat (important for intense cardio), it looks cheap to my aesthetic sensibilities. The silver clasp also looks cheap..
- Pointer function: First-world problems: due to the hybrid design, the hands can partially obscure the digital display depending on the time..
- How long does the battery of the GA-2100 last? According to Casio, the battery lasts around three years. That’s not a top-of-the-line figure, but perfectly adequate for everyday use.
In the next section, I’ll show you what I would look for when buying my next watch.
This is how you avoid typical buying mistakes.
- Choosing the wrong display: Anyone who absolutely needs to know the time at night and at dusk, or who trains for their marathon in complete darkness, should not choose ‘negative displays’ (dark background, light numbers).
- Underestimating the size: Even though it’s flat, it’s not a tiny dress watch – the sporty G-Shock design remains present.
- Band ignorance: The resin band is generally excellent. I personally will test a modding kit or a different band. Please decide for yourselves.
FAQ
- Did I regret the purchase? No, the watch looks stylish, is lightweight, and goes well with any outfit. Especially in black. Its features are perfectly adequate for everyday use.
- Is the product worth the money? Yes, the build quality and robustness are excellent for around 100 euros.
- Is it suitable for everyday use? Yes, it is one of the best ‘everyday carry’ watches.
- What are the long-term experiences? The carbon fiber case is extremely durable and hardly ages visually..
- Would I buy it again today? Without hesitation.
Final recommendation
After several months of daily use, I would buy the GA-2100 again. Not because it’s perfect, but because Casio has achieved a rare balancing act: The watch is as robust as a classic G-Shock, yet appears significantly more practical and stylish for everyday wear. Anyone who can live with the minor shortcomings of the strap and the legibility will find themselves with one of the most interesting classic watches of recent years..
Would I buy my current GA-2100 again? Absolutely: Yes.
You can find them here on Amazon → Casio GA-2100-1AER*