Casio F-91W vs Tissot Seastar 1000 Automatic
Casio's timepiece meets Tissot's diver
Quick Verdict
The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Tissot Seastar 1000 Automatic ($500–$1,000). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Seastar 1000 Automatic counters with Swiss Made craftsmanship and 300m (30 ATM) water resistance. Both are exceptional watches for their respective tiers.
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Specifications Compared
| Feature | Casio F-91W | Tissot Seastar 1000 Automatic |
|---|---|---|
| Price | Under $50 | $500–$1,000 |
| Case Size | 35mm | 40mm |
| Movement | Quartz Module 593 | Automatic Powermatic 80 (Caliber 80.111) |
| Caliber Type | Casio Digital Quartz (Battery) | ETA/Tissot Automatic |
| Power Reserve | 7-Year Battery | 80 Hours |
| Water Resistance | 30m (Splash Resistant) | 300m (30 ATM) |
| Crystal | Acrylic | Sapphire Crystal |
| Case Material | Resin | Stainless Steel |
| Origin | Casio (Japan) | Swiss Made |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Tissot's approach
The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Tissot Seastar 1000 Automatic offers Stainless Steel construction at 40mm with Sapphire Crystal. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Quartz Module 593 vs Automatic Powermatic 80 (Caliber 80.111)
The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Seastar 1000 Automatic uses the Automatic Powermatic 80 (Caliber 80.111) (ETA/Tissot Automatic, 80 Hours reserve) at 21,600 vph (3 Hz). The Seastar 1000 Automatic offers a longer power reserve.
Wearability & Fit
35mm vs 40mm — different wrist presence
At 35mm, the F-91W wears more compactly on smaller wrists compared to the Seastar 1000 Automatic at 40mm. Water resistance differs: 30m (Splash Resistant) vs 300m (30 ATM).
Value & Cost of Ownership
Casio sits in the lower tier
The Casio F-91W sits at Under $50 and the Tissot Seastar 1000 Automatic at $500–$1,000. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Sapphire Crystal and 80 Hours on the Seastar 1000 Automatic. Service intervals are typically 5-7 years for both.
Water Resistance
30m (Splash Resistant) vs 300m (30 ATM)
The F-91W is rated to 30m (Splash Resistant) while the Seastar 1000 Automatic handles 300m (30 ATM). The Seastar 1000 Automatic offers superior water resistance.
Our Verdict
Casio
F-91W
Choose the Casio F-91W if you prioritize Casio Digital Quartz (Battery) engineering, Casio (Japan) craftsmanship, and 30m (Splash Resistant) water resistance. At Under $50, it delivers Quartz Module 593 with 7-Year Battery power reserve.
Check Price on AmazonTissot
Seastar 1000 Automatic
Choose the Tissot Seastar 1000 Automatic if you value ETA/Tissot Automatic technology, Swiss Made heritage, and 40mm proportions. At $500–$1,000, the Automatic Powermatic 80 (Caliber 80.111) with 80 Hours power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio F-91W and Tissot Seastar 1000 Automatic represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Tissot delivers Swiss Made engineering.
Frequently Asked Questions
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How This Page Was Made
Our comparisons are generated from a hand-maintained specification database and reviewed under our editorial standards. We use AI tools to assemble pages from that data. We don’t invent specs: every number traces back to the database, and when we correct an entry, the fix is applied site-wide. As an Amazon Associate, The Horologist earns from qualifying purchases.