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
ModerateCase covers 64% of your modeled wrist width.
Physical footprint
Clear spaceEstimated clearance: 7.3 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 | Tissot Seastar |
|---|---|---|
| Pricing | ||
| MSRPG-Shock is $550 less at MSRP | $200 | $750 |
| Used Price (Low)G-Shock is $228.8 less at the low end | $90 | $319 |
| Used Price (High) | $650 | $585 |
| 30-Day Trend | ↓ -2.7% | ↓ -16.4% |
| Used Price Range | $90 - $650 | $319 - $585 |
| Identity | ||
| Style | Ana-Digi, Sports, Tool | Diver, Sports |
| Dimensions | ||
| DiameterSeastar is 4.4mm smaller | 40.4mm | 36mm |
| ThicknessSeastar is 1.3mm thinner | 11mm | 9.7mm |
| WeightG-Shock is 59g lighter | 55g | 114g |
| Lug Width | 16mm | 18mm |
| Lug to Lug | 46mm | 42mm |
| Case | ||
| Crystal | Mineral Crystal | Sapphire Crystal |
| Water ResistanceSeastar adds 100m water resistance | 200m (diving) | 300m (diving) |
| Bezel | Fixed | Unidirectional rotating |
1 field is 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 Tissot Seastar comparison is less about a universal winner and more about wrist presence versus easier fit, water-ready utility versus dressier everyday wear, ana-digi character versus diver versatility. Treat it as a value-versus-upgrade decision — confirm the extra spend solves a problem you will notice every week.
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 prefer more dial presence and a larger case feel; choose Tissot Seastar if you want a smaller case footprint on the wrist.
Choose Casio G-Shock GM-S2100 (small metal) when
Casio G-Shock GM-S2100 (small metal) is a better fit for buyers who want more wrist presence, low-maintenance daily wear, ana-digi styling.
Choose Tissot Seastar when
Tissot Seastar is a better fit for smaller wrists, low-maintenance daily wear, diver styling.
Movement and upkeep
Casio G-Shock GM-S2100 (small metal): quartz movement
Tissot Seastar: 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
Tissot Seastar: 36mm · L2L 42mm · 114g
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
Tissot Seastar: 300m
Water resistance is a meaningful separator here — the higher-rated option gives more flexibility for swimming or rougher daily use.
Price and value
Casio G-Shock GM-S2100 (small metal): $130
Tissot Seastar: $355
There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.
Style and use case
Casio G-Shock GM-S2100 (small metal): ana-digi
Tissot Seastar: diver
Casio G-Shock GM-S2100 (small metal) leans more ana-digi, while Tissot Seastar pulls toward diver 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
Tissot Seastar: sapphire crystal · steel
Crystal choice can change long-term wear expectations — one may prioritize scratch resistance while the other keeps cost or vintage feel in check.
Casio G-Shock GM-S2100 (small metal) is often the value play at current pricing, while Tissot Seastar makes more sense if you will use its extra features regularly.
There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.
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.
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Casio G-Shock
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Tissot Seastar
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Tissot Seastar — it is 42mm lug-to-lug versus 46mm, and lug-to-lug is what decides whether a watch overhangs a smaller wrist.
Tissot Seastar — it is rated 300m versus 200m. Both are in the same broad bracket, so treat this as a tiebreaker rather than a deciding factor.
Casio G-Shock GM-S2100 (small metal) is the value pick at roughly $225 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.
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