Head-to-Head Comparison

Casio F-91W vs Orient Sun & Moon

Casio's timepiece meets Orient's dress watch

Quick Verdict

The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Orient Sun & Moon ($250–$500). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Sun & Moon counters with Made in Japan craftsmanship and 50m (5 ATM) water resistance. Both are exceptional watches for their respective tiers.

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Casio F-91W

Casio

F-91W

Under $50

Orient Sun & Moon

Orient

Sun & Moon

$250–$500

Specifications Compared

FeatureCasio F-91WOrient Sun & Moon
PriceUnder $50$250–$500
Case Size35mm41.5mm
MovementQuartz Module 593Automatic Caliber F6B24
Caliber TypeCasio Digital Quartz (Battery)Orient In-House Automatic (Hacking, Hand-Winding)
Power Reserve7-Year Battery40 Hours
Water Resistance30m (Splash Resistant)50m (5 ATM)
CrystalAcrylicMineral Glass
Case MaterialResinStainless Steel
OriginCasio (Japan)Made in Japan

Category-by-Category Analysis

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Design & Aesthetics

Edge: Draw

Casio's design language vs Orient's approach

The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Orient Sun & Moon offers Stainless Steel construction at 41.5mm with Mineral Glass. Both represent their brand's distinct design philosophy and heritage.

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Movement & Performance

Edge: Orient

Quartz Module 593 vs Automatic Caliber F6B24

The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Sun & Moon uses the Automatic Caliber F6B24 (Orient In-House Automatic (Hacking, Hand-Winding), 40 Hours reserve) at 21,600 vph (3 Hz). The Sun & Moon offers a longer power reserve.

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Wearability & Fit

Edge: Casio

35mm vs 41.5mm — different wrist presence

At 35mm, the F-91W wears more compactly on smaller wrists compared to the Sun & Moon at 41.5mm. Water resistance differs: 30m (Splash Resistant) vs 50m (5 ATM).

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Value & Cost of Ownership

Edge: Casio

Casio sits in the lower tier

The Casio F-91W sits at Under $50 and the Orient Sun & Moon at $250–$500. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Mineral Glass and 40 Hours on the Sun & Moon. Service intervals are typically 5-7 years for both.

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Water Resistance

Edge: Orient

30m (Splash Resistant) vs 50m (5 ATM)

The F-91W is rated to 30m (Splash Resistant) while the Sun & Moon handles 50m (5 ATM). The Sun & Moon 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.

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Orient

Sun & Moon

Choose the Orient Sun & Moon if you value Orient In-House Automatic (Hacking, Hand-Winding) technology, Made in Japan heritage, and 41.5mm proportions. At $250–$500, the Automatic Caliber F6B24 with 40 Hours power reserve makes it a compelling choice.

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The Bottom Line

The Casio F-91W and Orient Sun & Moon represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Orient delivers Made in Japan engineering.

Frequently Asked Questions

Neither is objectively better — they serve different preferences. The Casio F-91W (Under $50) offers Quartz Module 593 with 7-Year Battery power reserve, while the Orient Sun & Moon ($250–$500) features Automatic Caliber F6B24 with 50m (5 ATM) water resistance. Choose based on your priorities: Casio (Japan) craftsmanship vs Made in Japan engineering.
The Casio F-91W offers better upfront value, sitting a tier lower at Under $50. However, the Orient Sun & Moon may justify its premium with superior finishing, heritage, or resale value.
Both are suitable for daily wear. The F-91W at 35mm with 30m (Splash Resistant) water resistance handles everyday situations. The Sun & Moon at 41.5mm with 50m (5 ATM) is similarly capable. The F-91W uses Acrylic while the Sun & Moon uses Mineral Glass.

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.