Side-by-side comparison of specifications and features
Compare visual case presence and physical footprint on one shared wrist. Measure your top-down wrist width for a stronger result; lug-to-lug is used when the catalog has it.
Medium (6.7″)
Estimated top width: 56.7 mm
Preliminary range: 54.7–61.8 mm.
Watch A
Visual presence
BoldCase covers 71% of your modeled wrist width.
Physical footprint
Clear spaceEstimated clearance: 5.3 mm per side.
Watch B
Visual presence
DominantCase covers 90% of your modeled wrist width.
Physical footprint
Near the edgeEstimated clearance: 0.8 mm per side.
Proportional guide only: visual presence and physical footprint do not predict comfort. Weight, thickness, caseback shape, rigid lugs, strap stiffness, wrist-bone prominence, wearing tension, bezel design, and case curvature change how a watch actually wears. Non-round silhouettes use a verified family shape and catalog dimensions where available; missing case height or width is estimated from a conservative family aspect ratio.
Start with the specifications that meaningfully differ. Expand the complete table for reference details and missing-data context.
| Specification | Casio G-Shock | Casio G-Shock GA-100 |
|---|---|---|
| Pricing | ||
| MSRPG-Shock GA-100 is $90 less at MSRP | $200 | $110 |
| New PriceG-Shock GA-100 is $7.8 less based on the current snapshot | $130 | $122 |
| Used Price (Low)G-Shock GA-100 is $35 less at the low end | $90 | $55 |
| Used Price (High) | $650 | $329 |
| 30-Day Trend | ↓ -2.7% | ↓ -7.9% |
| Used Price Range | $90 - $650 | $55 - $329 |
| Identity | ||
| Style | Ana-Digi, Sports, Tool | Sports, Tool |
| Dimensions | ||
| DiameterG-Shock is 10.8mm smaller | 40.4mm | 51.2mm |
| Thickness | 11mm | N/A |
| Lug to Lug | 46mm | 55mm |
| Case | ||
| Case Material | Stainless Steel | Resin |
2 fields are excluded from the differences view because one watch lacks comparable data. Use “All specs” to inspect those gaps.
This Casio G-Shock GM-S2100 (small metal) vs Casio G-Shock GA-100 comparison is less about a universal winner and more about wrist presence versus easier fit, ana-digi character versus sports versatility. Start with fit first — case width and lug-to-lug usually matter more than secondary features if wrist comfort is a concern.
Bottom line
Fit is a real separator here — compare case width and lug-to-lug before deciding, especially if wrist comfort matters more than headline features. Choose Casio G-Shock GM-S2100 (small metal) if you want a smaller case footprint on the wrist; choose Casio G-Shock GA-100 if you prefer more dial presence and a larger case feel.
Choose Casio G-Shock GM-S2100 (small metal) when
Casio G-Shock GM-S2100 (small metal) is a better fit for smaller wrists, low-maintenance daily wear, ana-digi styling.
Choose Casio G-Shock GA-100 when
Casio G-Shock GA-100 is a better fit for buyers who want more wrist presence, low-maintenance daily wear, sports styling.
Movement and upkeep
Casio G-Shock GM-S2100 (small metal): quartz movement
Casio G-Shock GA-100: quartz movement
Both use the same movement type, so maintenance differences are limited and fit or feature details should decide the purchase.
Size and wearability
Casio G-Shock GM-S2100 (small metal): 40.4mm · L2L 46mm · 55g
Casio G-Shock GA-100: 51.2mm · L2L 55mm
Fit is a real separator here — compare case width and lug-to-lug before deciding, especially if wrist comfort matters more than headline features.
Water resistance
Casio G-Shock GM-S2100 (small metal): 200m
Casio G-Shock GA-100: 200m
Water resistance is similar on paper, so focus on fit, features, and price instead.
Price and value
Casio G-Shock GM-S2100 (small metal): $130
Casio G-Shock GA-100: $122
These two often land in a similar price band — which usually means fit, features, and current deal quality matter more than the sticker price.
Style and use case
Casio G-Shock GM-S2100 (small metal): ana-digi
Casio G-Shock GA-100: sports
Casio G-Shock GM-S2100 (small metal) leans more ana-digi, while Casio G-Shock GA-100 pulls toward sports use case — pick the one that matches how you will actually wear it.
Crystal and materials
Casio G-Shock GM-S2100 (small metal): mineral crystal · steel
Casio G-Shock GA-100: mineral crystal · resin
Materials are broadly similar, so finish, fit, and price will matter more than the materials list alone.
Casio G-Shock GA-100 usually offers the lower entry price — confirm current listings because marketplace pricing can move quickly.
These two often land in a similar price band — which usually means fit, features, and current deal quality matter more than the sticker price.
Check current deals on Amazon and eBay using the buttons below — listing prices, seller quality, and condition can change quickly.
Prices change often, so compare the latest listings and condition options before you buy.
WatchCompared may earn a commission from qualifying purchases through affiliate links. This does not change your price.
Casio G-Shock
Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.
Casio G-Shock GA-100
Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.
Casio G-Shock GM-S2100 (small metal) — it is 46mm lug-to-lug versus 55mm, and lug-to-lug is what decides whether a watch overhangs a smaller wrist.
They are rated the same, so water resistance will not decide this. Choose on strap material and how much you mind scratching the case.
Casio G-Shock GA-100 is the value pick at roughly $8 less. Pay more only if a specific difference above matters to you — otherwise the cheaper one is the smarter buy. Confirm live listings, since marketplace pricing moves.
Evidence & Method
This page currently relies on normalized catalog fields and calculated differences. No external reviewer observation is used in its verdict.
Compare Watches
Start a new multi-watch comparison
Compare Watch Prices
US-focused price comparison workflow
Watch Fit Chart
Size and wrist-fit guidance
Related Budget Page
Compare similar watches in the same price band
Watch Buying Guides
Read movement, fit, and buying guides before deciding
Smartwatch Compare Hub
Compare Apple, Garmin, Samsung, and more if you are cross-shopping smartwatches
Casio G-Shock GMA-S2100 (small) vs Casio G-Shock GA-100
tier2High-intent comparison page
Casio G-Shock GM-S2100 (small metal) vs Tissot PRX
tier2High-intent comparison page
Casio G-Shock GM-S2100 (small metal) vs Casio G-Shock GMA-S2100 (small)
tier2High-intent comparison page
Casio G-Shock GM-S2100 (small metal) vs Tissot Seastar
tier2High-intent comparison page
Casio G-Shock GM-S2100 (small metal) vs Tissot Seastar 1000
tier2High-intent comparison page
Continue comparing specs and pricing, or start a new shortlist with the comparison tool and browse pages.
Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.
Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.
You can compare up to 10 watches. Browse watches and click "Add to Compare" to add more.
