Head-to-Head Comparison

Updated September 5, 2026

Casio F-91W vs Casio Pro Trek PRW3500T-7

Casio's timepiece meets Casio's diver

Quick Verdict

The Casio F-91W (Under $50) offers Casio Digital Quartz (Battery) precision in the tier below the Casio Pro Trek PRW3500T-7 ($250–$500). The F-91W measures 35mm and is rated 30m (Splash Resistant). The Pro Trek PRW3500T-7 counters with Casio (Japan) craftsmanship and 200m (20 ATM) water resistance. Both are exceptional watches for their respective tiers.

CasioF-91WUnder $50 Check price CasioPro Trek PRW3500T-7$250–$500 Check price

Transparency — We earn a small commission on purchases made through our Amazon links. This doesn't affect our editorial independence.

Casio

F-91W

Under $50

Check Price Full Review

Casio

Pro Trek PRW3500T-7

$250–$500

Check Price Full Review

Specifications Compared

Feature	Casio F-91W	Casio Pro Trek PRW3500T-7
Price	Under $50	$250–$500
Case Size	35mm	56.9 × 53.4 × 14.8mm
Movement	Quartz Module 593	Tough Solar (Solar Quartz), Radio-Controlled
Caliber Type	Casio Digital Quartz (Battery)	Tough Solar Quartz, Multi-Band 6
Power Reserve	7-Year Battery	Tough Solar (Rechargeable)
Water Resistance	30m (Splash Resistant)	200m (20 ATM)
Crystal	Acrylic	Mineral Glass
Case Material	Resin	Resin / Stainless Steel, Titanium Bracelet
Origin	Casio (Japan)	Casio (Japan)

Category-by-Category Analysis

🎨

Design & Aesthetics

Edge: Draw

Casio's design language vs Casio's approach

The Casio F-91W features a Resin case at 35mm with Acrylic protection. The Casio Pro Trek PRW3500T-7 offers Resin / Stainless Steel, Titanium Bracelet construction at 56.9 × 53.4 × 14.8mm with Mineral Glass. Both represent their brand's distinct design philosophy and heritage.

⚙️

Movement & Performance

Edge: Casio

Quartz Module 593 vs Tough Solar (Solar Quartz), Radio-Controlled

The F-91W runs the Quartz Module 593 (Casio Digital Quartz (Battery), 7-Year Battery power reserve) at standard frequency. The Pro Trek PRW3500T-7 uses the Tough Solar (Solar Quartz), Radio-Controlled (Tough Solar Quartz, Multi-Band 6, Tough Solar (Rechargeable) reserve) at standard. The F-91W edges ahead on power reserve.

📏

Wearability & Fit

Edge: Casio

35mm vs 56.9 × 53.4 × 14.8mm — different wrist presence

At 35mm, the F-91W wears more compactly on smaller wrists compared to the Pro Trek PRW3500T-7 at 56.9 × 53.4 × 14.8mm. Water resistance differs: 30m (Splash Resistant) vs 200m (20 ATM).

💰

Value & Cost of Ownership

Edge: Casio

Casio sits in the lower tier

The Casio F-91W sits at Under $50 and the Casio Pro Trek PRW3500T-7 at $250–$500. On the specs that outlast any price: the F-91W uses Acrylic with 7-Year Battery, against Mineral Glass and Tough Solar (Rechargeable) on the Pro Trek PRW3500T-7. Service intervals are typically 5-7 years for both.

💧

Water Resistance

Edge: Casio

30m (Splash Resistant) vs 200m (20 ATM)

The F-91W is rated to 30m (Splash Resistant) while the Pro Trek PRW3500T-7 handles 200m (20 ATM). The Pro Trek PRW3500T-7 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 Amazon

Casio

Pro Trek PRW3500T-7

Choose the Casio Pro Trek PRW3500T-7 if you value Tough Solar Quartz, Multi-Band 6 technology, Casio (Japan) heritage, and 56.9 × 53.4 × 14.8mm proportions. At $250–$500, the Tough Solar (Solar Quartz), Radio-Controlled with Tough Solar (Rechargeable) power reserve makes it a compelling choice.

Check Price on Amazon

Try Prime Free — Free Shipping on Both Watches Students & 18–24: start Prime for Young Adults free

The Bottom Line

The Casio F-91W and Casio Pro Trek PRW3500T-7 represent two distinct approaches to fine watchmaking — the Casio bringing Casio (Japan) tradition while Casio delivers Casio (Japan) engineering.

Frequently Asked Questions

For water, the Casio Pro Trek PRW3500T-7 is rated 200 m against 30 m, which is the difference between swimming and diving on one side and splashes on the other. On price, the Casio F-91W sits a band lower (Under $50 against $250–$500), so it is the cheaper way into the category. Neither is better at everything; the spec table above shows movement, case size, water resistance and crystal side by side so you can weigh what matters to you. We do not test units, so this is the makers' data, not a bench result.

The Casio F-91W offers better upfront value, sitting a tier lower at Under $50. However, the Casio Pro Trek PRW3500T-7 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 Pro Trek PRW3500T-7 at 56.9 × 53.4 × 14.8mm with 200m (20 ATM) is similarly capable. The F-91W uses Acrylic while the Pro Trek PRW3500T-7 uses Mineral Glass.

More Comparisons

Casio Pro Trek PRG601 vs PRW3500T

Two Triple Sensor solar Pro Treks

Tag Heuer Carrera Chronograph vs Casio F-91W

Tag Heuer's chronograph meets Casio's timepiece

Tag Heuer Carrera Chronograph vs Casio Pro Trek PRW3500T-7

Tag Heuer's chronograph meets Casio's diver

Explore These Watches

Casio F-91W — Full Review Casio Pro Trek PRW3500T-7 — Full Review Browse All Guides

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.