Casio F-91W vs Oris Aquis Date Calibre 400
Casio's timepiece meets Oris's diver
Quick Verdict
The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Oris Aquis Date Calibre 400 ($2,500–$5,000). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Aquis Date Calibre 400 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 | Oris Aquis Date Calibre 400 |
|---|---|---|
| Price | Under $50 | $2,500–$5,000 |
| Case Size | 35mm | 41.5mm |
| Movement | Quartz Module 593 | Automatic Calibre 400 |
| Caliber Type | Casio Digital Quartz (Battery) | Oris In-House Manufacture |
| Power Reserve | 7-Year Battery | 120 Hours (5 Days) |
| Water Resistance | 30m (Splash Resistant) | 300m (30 ATM) |
| Crystal | Acrylic | Sapphire Crystal with Anti-Reflective Coating |
| Case Material | Resin | Stainless Steel |
| Origin | Casio (Japan) | Swiss Made |
Category-by-Category Analysis
Design & Aesthetics
Casio's design language vs Oris's approach
The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Oris Aquis Date Calibre 400 offers Stainless Steel construction at 41.5mm with Sapphire Crystal with Anti-Reflective Coating. Both represent their brand's distinct design philosophy and heritage.
Movement & Performance
Quartz Module 593 vs Automatic Calibre 400
The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Aquis Date Calibre 400 uses the Automatic Calibre 400 (Oris In-House Manufacture, 120 Hours (5 Days) reserve) at 28,800 vph (4 Hz). The Aquis Date Calibre 400 offers a longer power reserve.
Wearability & Fit
35mm vs 41.5mm — different wrist presence
At 35mm, the F-91W wears more compactly on smaller wrists compared to the Aquis Date Calibre 400 at 41.5mm. 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 Oris Aquis Date Calibre 400 at $2,500–$5,000. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Sapphire Crystal with Anti-Reflective Coating and 120 Hours (5 Days) on the Aquis Date Calibre 400. 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 Aquis Date Calibre 400 handles 300m (30 ATM). The Aquis Date Calibre 400 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 AmazonOris
Aquis Date Calibre 400
Choose the Oris Aquis Date Calibre 400 if you value Oris In-House Manufacture technology, Swiss Made heritage, and 41.5mm proportions. At $2,500–$5,000, the Automatic Calibre 400 with 120 Hours (5 Days) power reserve makes it a compelling choice.
Check Price on AmazonThe Bottom Line
The Casio F-91W and Oris Aquis Date Calibre 400 represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Oris 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.