Casio G-Shock GM-2100 Color Variants (GM-2100B, GM-2100C, GM-2100D): Current Prices, JDM Listings, Market Analysis

The Casio G-Shock GM-2100 series occupies a specific corner of the G-Shock market where the metal-bezel construction of the GA-2100 platform meets color-variant releases aimed squarely at the Japanese domestic market. The GM-2100B, GM-2100C, and GM-2100D are tracked here as a group because their pricing tends to move together and JDM supply is often the most accessible route for buyers outside Japan. Tonbo monitors these references because the gap between Japanese flea-market pricing and US resale pricing creates occasional value windows worth flagging. At a US median of $310, these are mid-range G-Shock acquisitions that reward timing and condition awareness.

Current US Market Value

The current US median for the Casio G-Shock GM-2100 Color Variants sits at $310, with the middle 50% of transactions falling between $250 and $390. That spread is meaningful. A $140 range across the interquartile band tells you condition and colorway both matter to buyers at this price tier. It is worth being direct about the data quality here: this estimate is drawn from a sample size of four data points, and the comp source is operator-estimated rather than pulled from a dense transaction feed. The confidence rating is 🟠 Estimate only. That does not make the figure useless, but it does mean you should treat the $310 median as a reasonable anchor rather than a settled market price. As more transaction data accumulates, that figure will sharpen. For now, use it directionally when evaluating whether a specific listing, especially one showing a GM-2100B for sale at a given ask, represents fair value or an outlier.

Active JDM Listings

Japan is showing active supply across both flea-market and shop channels right now, with three listings appearing on June 15 alone. The condition spread is notable, ranging from near-unused pieces to worn examples, and that variance maps directly onto the price difference between listings. Anyone looking to buy GM-2100B Japan-sourced should pay close attention to condition grading, which on Japanese platforms tends to be more conservative and reliable than US equivalents.

• ¥32,000 on Yahoo Flea Market (June 15) , listed as close to unused, representing the higher end of current JDM asking prices
• ¥24,600 on Yahoo Shop (June 15) , condition listed as unknown, mid-range pricing for the platform type
• ¥13,500 on Yahoo Flea Market (June 15) , described as a little damaged or dirty, significantly discounted relative to the near-unused example
• The spread between the lowest and highest ask on a single day is roughly ¥18,500, underlining how much condition drives pricing in this reference group
• Shop listings (Yahoo Shop) tend to carry some implicit condition vetting relative to individual flea-market sellers, though condition disclosures can still vary

Recent Alert History

No strict or opportunity alerts have fired for the GM-2100 color variant group in the past 90 days. That is an honest read of the data, not a gap in coverage. It means no listing has cleared Tonbo's threshold filters for either a strong deal signal or a strict undervaluation flag during that window. This could reflect relatively stable JDM pricing, thin listing volume at the right price points, or both. Buyers who want to be notified the moment a qualifying listing appears, rather than checking manually, will find the alert infrastructure useful. You can review how Tonbo's signal tiers work at tonbomarket.com/signals.

Japan vs. US Price Gap

At current exchange rates, the near-unused ¥32,000 listing converts to roughly $210 to $215 USD before any fees or shipping, which sits below the US p25 floor of $250 and well below the $310 median. That gap reflects a combination of factors: US buyers absorb proxy service fees, international shipping, and the convenience premium of purchasing domestically rather than navigating Japanese auction platforms. The worn ¥13,500 listing is a different story, likely below the threshold of what US buyers would accept given condition, but it illustrates how wide the JDM condition range can run. The primary risk factor on GM-2100B price estimates at this stage is comp thinness. Four data points is a starting set, not a stable market picture, and anyone making purchase decisions should treat that context seriously. Curated deal flow from Japan for this reference group is tracked at tonbomarket.com/deals.

Track Casio G-Shock GM-2100 Color Variants on Tonbo

Tonbo is free to start. The Collector tier at tonbomarket.com/dashboard gives you a five-model watchlist, JDM listing visibility, and price tracking for the GM-2100B and its siblings with no credit card required. If you want real-time Discord alerts when a qualifying listing appears, the Member tier runs $10 per month and adds that layer on top of the free feature set. Given the thin comp data on this reference group, having automated eyes on the JDM market is more useful here than on heavily traded models where price discovery is already efficient.