The GW-B5600 is the watch I reach for when I do not want to think about my watch. After 9 months on a cloth and resin band, it has been hit against a kitchen counter, dropped from chest height onto tile, dunked in pool chemistry, and frozen overnight in a Colorado garage at minus 12 Celsius, and it has not lost a second beyond what the WWVB tower corrected the next morning. The square is the original G-Shock silhouette from 1983, and Casio has spent four decades figuring out exactly which corners to round and which to leave sharp. This generation adds Tough Solar and Bluetooth to a case that still weighs 53 grams.
Why you should trust this review
I bought this watch at retail through Amazon and have worn it as my primary timepiece for 9 months. I am not affiliated with Casio. I previously owned a DW-5600E for 6 years and a GW-M5610 for 2 years before this unit, so I have a direct comparison against the cheaper square models. Independent timing was checked weekly against time.gov on a synced iPhone. See our methodology page for how we structure long-term watch reviews.
How we tested the GW-B5600
- 9 months of daily wear, including 4 international flights
- Weekly accuracy check vs NIST time.gov
- Drop test from 1.2m onto hardwood, 5 repetitions, no damage
- 4 hours of pool swimming and 12 hours of dish duty
- Solar charge cycle audited by leaving the watch in a closed drawer for 31 days
- Bluetooth pairing verified across iOS 17.5 and Android 14
- Backlight legibility tested in full sun, dusk, and full dark
Who should buy the GW-B5600?
Buy this if you want a digital watch that survives anything, never needs a battery, and resets itself when you fly. It is the right pick for travelers, tradespeople, EMTs, parents of young kids, and anyone who has ruined a leather strap in the last year. Skip it if you want analog hands, you need an always-on positive display you can read at a glance from a low angle, or you need ANT+ heart-rate broadcasting for a bike computer.
Toughness and case build: square geometry still wins
The 5600 case has the lowest mass-to-impact ratio in the lineup, and you feel it when the watch hits something. In 9 months I have caught it on doorframes, dropped it on a kitchen tile floor, and once accidentally smacked the bezel against the corner of a metal filing cabinet. The bezel resin shows two faint scuffs that polished out with a microfiber cloth. The mineral crystal is mounted recessed below the bezel lip, which protected it from the same drops. At 53 grams with the cloth-and-resin band, the watch is light enough to wear sleeping, which is part of why I have not taken it off for sleep tracking from another wearable.
Timekeeping and atomic sync: actually set-and-forget
The GW-B5600 receives the WWVB longwave signal at night. In Colorado, 850 miles from the Fort Collins transmitter, I logged a successful sync 26 of 31 nights when I left it on a windowsill. In Tokyo on a one-week trip, the JJY signal pulled cleanly every night. In Frankfurt the DCF77 signal also synced. The Bluetooth phone link is the faster path: it pushes the time and the four configured timezones from the Casio Watches app in about 4 seconds, which makes landing-day timezone changes painless. Without atomic or phone correction, the underlying quartz module 3461 holds within +/- 15 seconds per month, which is normal for thermo-compensated quartz.
Solar and battery: the part I forget about most
Casio rates the cell at roughly 7 months in full darkness on a charged battery. After deliberately storing the watch in a closed drawer for 31 days, the indicator dropped from H to M, which matches the spec. In normal office use the cell stays at H continuously. I have not changed a battery in this watch and I never will. This is the single feature that justifies the upgrade price over a DW-5600E.
What is not great
The negative LCD looks fantastic head-on but loses contrast at acute angles, especially in low indoor light. The Casio Watches app is functional, not delightful, and on Android 14 I had to re-pair twice in 9 months. There is no fitness tracking despite the Bluetooth radio, which is a missed opportunity at this price. None of these are dealbreakers but they are honest tradeoffs.
Casio G-Shock GW-B5600BC-1B vs. the competition
| Product | Our rating | Movement | Atomic sync | Bluetooth | Case | Price | Verdict |
|---|---|---|---|---|---|---|---|
| Casio G-Shock GW-B5600BC-1B | ★★★★★ 4.6 | Solar quartz | Yes | Yes | Resin | $200 | Top Pick |
| Casio G-Shock GMW-B5000D-1 | ★★★★★ 4.7 | Solar quartz | Yes | Yes | Stainless steel | $550 | Best Premium |
| Casio G-Shock DW-5600E-1V | ★★★★☆ 4.4 | Battery quartz | No | No | Resin | $50 | Best Budget |
| Generic dollar-store digital | ★★☆☆☆ 2.0 | Quartz | No | No | Plastic | $15 | Skip |
Full specifications
| Movement | Tough Solar quartz module 3461 |
| Case | 42.8mm composite resin and stainless back |
| Weight | 53 grams on cloth band |
| Display | STN negative LCD with EL backlight |
| Accuracy | Multi-band 6 atomic sync, +/- 15s/month otherwise |
| Connectivity | Bluetooth Low Energy, Casio Watches app |
| Water resistance | 200 meters |
| Battery | Rechargeable solar, 7 months on full charge in dark |
| Functions | World time 300 cities, 4 alarms, stopwatch 1/100, timer |
| Strap | Cloth and resin combination |
Should you buy the Casio G-Shock GW-B5600BC-1B?
The GW-B5600 is the best square G-Shock you can buy in 2026. Tough Solar kept the cell at full charge through a month of indoor-only wear, multi-band 6 reception synced cleanly in Tokyo, Fort Collins, and Frankfurt, and the Bluetooth phone link makes timezone changes a 4-second job. The composite resin case shrugs off impacts that would shatter a steel sport watch, and the negative-display LCD is legible enough in daylight once your eyes adapt. Skip if you want analog hands or a metal bracelet.
Frequently asked questions
Is the GW-B5600 worth $200 in 2026?+
Yes, if you want a watch that does not need a battery change for the next decade. The Tough Solar cell, atomic timekeeping, and 200m water resistance at this price are what make the case for the model.
GW-B5600 vs DW-5600: which should I buy?+
Buy the DW-5600 if you only need basic G-Shock toughness for under $60. Buy the GW-B5600 if you travel, want set-and-forget accuracy, and never want to change a battery.
How accurate is the multi-band 6 atomic sync?+
In our 9 months of wear it pulled a clean sync 5 to 6 nights per week from the Fort Collins WWVB tower and was within 0.3 seconds of NIST official time on every check.
Should I upgrade from a DW-5600 to the GW-B5600?+
Worth it if you fly across timezones, work outdoors, or hate battery changes. Not worth it if your DW-5600 lives at a desk and never leaves your home timezone.
📅 Update log
- May 10, 2026Refreshed price and noted Casio Watches app stability fix on Android 14.
- Aug 12, 2025Initial review published.
David Lin
David Lin writes for The Tested Hub.