Digital comparison
Casio F-91W vs Casio F108WH-1A Illuminator
Verdict. Today the Casio F108WH-1A Illuminator (F108WH-1A) is the better value by our formula: Value Score 100 vs 88, with 41 spec points at $20.97. The other watch costs $2.02 less. Prices as of November 3, 2026, 18:15 UTC.
Side by side
Casio F-91W vs Casio F108WH-1A Illuminator: specs and price
| Spec |  Casio F-91W F-91W-1 · priced variant of 2 |  Casio F108WH-1A Illuminator F108WH-1A |
|---|---|---|
| Price on Amazon today | $18.95 | $20.97 |
| Value Score (within type) | 88 | 100 |
| Spec points | 29 | 41 |
| Spec points per $100 | 153.0 | 195.5 |
| Movement | Digital quartz | Digital quartz |
| Power reserve | — | — |
| Crystal | Acrylic | Acrylic |
| Water resistance | — | 100 m |
| Screw-down crown | No | No |
| Case diameter | 35.2 mm | — |
| Lug-to-lug | 38.2 mm | — |
| Thickness | 8.5 mm | — |
| Lug width | — | — |
| Fits wrist from | ≥ 13.8 cm (5.4″) | — |
| Strap / bracelet | Resin | Resin |
| Made in | — | — |
| Amazon sales rank | #1 | #4 |
FAQ
Questions about the Casio F-91W and the Casio F108WH-1A Illuminator
Which is cheaper on Amazon today?
As of November 3, 2026, 18:15 UTC, the Casio F-91W (F-91W-1) is $18.95 and the Casio F108WH-1A Illuminator (F108WH-1A) is $20.97; the difference is $2.02. Amazon's price at checkout applies.
Context
Where both sit among basic digital watches
| # | Watch | Movement | Crystal | Water res. | Case diameter × lug-to-lug | Fits wrist | Spec pts | Price | Value Score | Buy |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | | Digital quartz | Acrylic | 100 m | — | — | 41 | $20.97 | 100 | Amazon |
| 2 | | Digital quartz | Acrylic | — | 35.2 × 38.2 mm | ≥ 13.8 cm (5.4″) | 29 | $18.95 | 88 | Amazon |
| 3 |  | Digital quartz | Acrylic | 100 m | — | — | 41 | $29.92 | 84 | Amazon |
| 4 |  | Digital quartz | Mineral | 200 m | — | — | 49 | $42.98 | 76 | Amazon |
| 5 |  | Digital quartz | Acrylic | 100 m | 42.1 × 45 mm | ≥ 16.2 cm (6.4″) | 41 | $37.98 | 74 | Amazon |
| 6 |  | Digital quartz | Acrylic | — | 33.2 × 36.8 mm | ≥ 13.2 cm (5.2″) | 32 | $29.92 | 74 | Amazon |
| 7 |  | Digital quartz | Acrylic | — | 36.3 × 38.6 mm | ≥ 13.9 cm (5.5″) | 32 | $29.92 | 74 | Amazon |
| 8 |  | Digital quartz | Acrylic | 100 m | — | — | 41 | $39.95 | 72 | Amazon |
| 9 |  | Digital quartz | Acrylic | 100 m | 42.1 × 45 mm | ≥ 16.2 cm (6.4″) | 44 | $48.88 | 68 | Amazon |
| 10 |  | Solar digital | Acrylic | 100 m | — | — | 47 | $53.95 | 67 | Amazon |
| 11 |  | Digital quartz | Acrylic | 100 m | 38 mm | — | 41 | $47.15 | 67 | Amazon |
Amazon.com prices as of November 3, 2026, 18:15 UTC — details. third-party = sold by a marketplace seller, not Amazon (warranty may differ); ships later = not in stock today, never crowned best value.