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Scan for outdated or missing drivers - takes under a minuteDriver Scan →Repair Windows errors before they cause bigger problemsFix Now →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →The Casio G-Shock Gulfmaster GWNQ1000-1A is a large, feature-dense marine watch whose standout capability is a depth sensor alongside compass, pressure, temperature and altitude readings. Casio’s US site identifies the GWNQ1000-1A as a Gulfmaster; the detailed specifications below are for the distinct Japanese-market GWN-Q1000A-1AJF variant, so confirm the exact suffix before applying them to a listing. This is a specification-led review, not a hands-on test.
What is the GWNQ1000-1A?
Casio places the GWNQ1000-1A in its G-Shock MASTER OF G – SEA Gulfmaster line. The concept is a tough, sensor-equipped watch for marine settings, combining analog-digital timekeeping with environmental readings and tide-related information. The official US product page confirms the model identity, but does not by itself establish that the watch is currently in stock: Casio America’s GWNQ1000-1A page.
Detailed figures in this review come from Casio Japan’s page for the GWN-Q1000A-1AJF, a specific Japanese reference. They should not be assumed to describe every GWN-Q1000 family suffix or every regional version: Casio Japan’s GWN-Q1000A-1AJF page.
What does the GWN-Q1000A-1AJF’s quad sensor measure?
Casio’s specification page lists the following sensor functions for the GWN-Q1000A-1AJF. These are manufacturer-stated capabilities and ranges, not independently measured accuracy or performance results.
#1 Best Overall
- Radio frequencies: 77.5 kHz (DCF77: Germany); 60 kHz (MSF: UK); 60 kHz (WWVB: USA); 40 kHz (JJY: Fukushima, Japan) / 60 kHz (JJY: Kyushu, Japan); 68.5 kHz (BPC: China)
- Radio wave reception: Automatic reception up to six times a day (except for use in China: up to five times a day); manual reception
- Digital compass: Measures and displays direction as one of 16 points with the second hand; measuring range: 0 to 359; measuring unit: 1; 60 seconds continuous measurement; bidirectional calibration and magnetic declination correction
- Barometer: Measuring range: 260 hPa to 1,100 hPa (7.65 to 32.45 inHg); measuring unit: 1 hPa (0.05 inHg); atmospheric pressure change indicator (10 hPa); atmospheric pressure tendency graph (past 20 hours graph display); barometric pressure tendency
- Altimeter: Measuring range: -700m to 10,000m (-2,300 to 32,800 ft); measuring unit: 1m (5 ft); altitude change indicator (100 m / 1000 m); others: measurement interval setting (every 5 seconds / every 2 minutes) (1 second for first three minutes on
- Direction: Compass readings in 16 directions and from 0–359°, with continuous direction measurement for up to 60 seconds.
- Atmospheric pressure: 260–1,100 hPa.
- Altitude: −700 to 10,000 m.
- Water depth: 0–50 m, displayed in 0.1 m units.
- Temperature: −10 to 60 °C.
The depth range is a measurement specification, not evidence that the watch replaces dive instrumentation or carries a diving-safety certification. The product page does not make those claims.
Case, materials and wearability
For the GWN-Q1000A-1AJF, Casio lists a 48 × 57.3 × 17 mm case and a weight of 113 g. The case and bezel combine resin and stainless steel, while the band is resin. Listed construction features include shock resistance, 20-bar water resistance, an anti-reflective-coated sapphire crystal and a screw-lock crown.
Rank #2
- Super Matte Finish, Shock Resistant, 200M water resistance, LED light (Super illuminator), World time, Stopwatch, Countdown timer, 5 daily alarms, Hourly time signal, Hand shift feature
- Full auto-calendar, 12/24-hour format, Analog: 2 hands (hour, minute (hand moves every 20 seconds)), Digital: Hour, minute, second, pm, month, date, day, Approx. battery life: 5 years on CR2016
- Quartz Movement. Measuring capacity is 23:59'59.99"
- Case Diameter: 52.8mm
- Water resistant 200m (660ft): in general, suitable for professional marine activity and serious surface water sports, but not diving
The 57.3 mm width and 17 mm thickness make this a substantial watch on paper. That size may be a trade-off for someone seeking a broad sensor display and marine functions, but the dimensions alone cannot establish how it will fit or feel on an individual wrist. Try the exact reference if fit is a deciding factor.
Timekeeping, power and other functions
Solar charging and radio time calibration
The Japanese variant uses Casio Tough Solar and Multi Band 6 time calibration. Casio specifies reception for Japan, North America, Europe and China, subject to compatible home-city settings and reception conditions. If radio reception is unavailable, the stated ordinary quartz accuracy is an average of ±15 seconds per month. Casio lists approximately six months of operation from a full charge without solar generation under function use, or approximately 21 months in power-saving state.
Rank #3
- Metal-clad daring meets sophisticated gleam in this Casio G-Shock that delivers Smartphone Link via Bluetooth(R) and Tough Solar charging system, all in a meticulously finished metal design with iconic octagonal bezel
- This model features a blue metallic vapor deposition dial that is complemented by a black band made of environmentally responsible bio-based resin
Marine and everyday features
The GWN-Q1000A-1AJF specification page also lists a tide graph, moon age, sunrise and sunset display, world time for 48 cities across 31 time zones plus UTC, a stopwatch, timer, five alarms and dual LED illumination. These features broaden its usefulness beyond sensor readings, though their presence does not tell you whether the analog-digital display will suit your preferences; check the face and controls in person or through clear product images.
Should you buy a Gulfmaster?
The GWNQ1000-1A makes the most sense to a buyer who specifically wants a rugged-looking, analog-digital marine watch with a broad set of sensors. The documented Japanese variant’s depth measurement is a meaningful distinction from Gulfmaster options that focus on other sensor combinations. For general timekeeping, a smaller or simpler watch may be easier to wear and operate; the Q1000’s appeal depends on whether its specialized functions justify its size and complexity for your use.
Rank #4
- Band Size: Mens-Standard
- Shock Resistant
- Auto LED Light with Afterglow
- Magnetic Resistant
Before choosing one, compare the exact reference and market rather than relying on the Gulfmaster name alone. Casio’s related GWN-1000 family page describes a triple-sensor line with tide graph and pressure-tendency functions, but those details should not be transferred to a Q1000: Casio Europe’s GWN-1000 family page.
- Check whether the listing is GWNQ1000-1A, GWN-Q1000A-1AJF or another suffix.
- Compare sensor functions, especially whether the reference includes water-depth measurement.
- Compare case dimensions and weight, crystal material, solar charging and radio-time support.
- Consider whether the analog-digital layout and illumination meet your readability needs.
Availability and buying an older reference
Casio Japan gives September 2017 as the release month for GWN-Q1000A-1AJF and marks that reference as production ended. Its page shows a Japanese suggested retail price of ¥85,800 including tax at the time listed; that is a historical regional price, not a current valuation. This does not establish the production or stock status of every suffix or market. Casio’s US product page identifies GWNQ1000-1A but does not prove new inventory, and current seller stock, resale value and asking prices have not been verified.
Best Value
- Iconic G-SHOCK Square Design – The legendary square case that started it all, delivering timeless style and the rugged durability G-SHOCK is known for.
- Shock Resistant & 200M Water Resistant – Built to withstand impacts, swimming, snorkeling, and demanding everyday use.
- Super Illuminator LED Backlight – Bright white LED with afterglow ensures excellent readability in low-light conditions.
- Essential Digital Features – Includes 1/100-second stopwatch, 24-hour countdown timer, multi-function alarm, flash alert, and full auto-calendar.
- Reliable 5-Year Battery Life – Powered by a CR2016 battery for long-lasting performance with minimal maintenance.
If buying a discontinued or older watch, check the seller’s stated reference, condition, included accessories and return terms. For replacement bands or bezel components, CasioPart associates GWNQ1000-1A with module 5477 and lists parts; verify the exact part number against the watch and confirm inventory before ordering: CasioPart’s GWNQ1000-1A parts listing.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
