Casio has launched the GBX-H5600KI-5, the latest addition to its surf-focused G-LIDE lineup and the fourth signature model developed with professional surfer Kanoa Igarashi. While it carries the iconic G-Shock name, this new smartwatch leans heavily into fitness features like an optical heart rate sensor and tide charts designed for water sports enthusiasts. Pre-orders have already opened in Japan, with shipments slated for later this month.
This move is a natural progression for Casio as it competes with fitness watch heavyweights like Garmin, Apple, and Suunto. Casio’s edge remains its shock-resistant G-Shock casing and instantly recognizable design. The company has flirted with fitness tracking in rugged watches before, but the GBX-H5600KI-5 specifically targets surfers and athletes spending significant time in and around water.
Casio G-LIDE GBX-H5600KI-5 specifications
The GBX-H5600KI-5 adopts the classic square G-Shock case shape but upgrades far beyond simple digital timekeeping. Casio equips it with an optical heart rate sensor and a 3-axis accelerometer, while workout analytics are powered by Polar’s well-established algorithms. This enables the watch to track training load, recovery pace, and sleep quality – features Polar has perfected in premium wearables and that Casio has integrated into its more sports-focused offerings.
- Optical heart rate sensor
- 3-axis accelerometer
- MIP LCD display for better outdoor visibility
- Bluetooth connectivity with Casio Watches app
- 200 meters water resistance
- Shock-resistant G-Shock body
The watch supports running and walking with metrics like pace, distance, and stride length. But its real strength lies at sea. It displays lunar phases, sunrise/sunset times, and, crucially, tide charts. Through the Casio Watches app, users can set tide data for around 3,300 locations globally via Bluetooth. The app also handles automatic time sync, an activity log, and basic smartphone notifications.
Casio chose a memory-in-pixel (MIP) LCD screen over OLED, which might look less flashy but offers far better outdoor visibility and battery efficiency – a staple choice for many sports watches like Garmin Instinct and some Coros models. This makes the watch easier to read in sunlight and extends runtime between charges.
The case and strap use bio-polymer materials, featuring a color scheme inspired by the coastal rock formations of Ericeira, Portugal – home to Igarashi’s training grounds. The watch sports a brown base with purple dial accents, and Casio notes that the resin pattern varies slightly between units. The watch weighs 47 grams.
Casio G-LIDE GBX-H5600KI-5 price and availability
In Japan, the GBX-H5600KI-5 is available for pre-order at 50,600 yen (around $314). Shipments are expected before the end of the month. Battery life varies with usage: Casio promises up to 35 hours with continuous heart rate monitoring and about a month in standard watch mode without active sensors.
Charging is via Casio’s proprietary USB Type-A cable, complemented by solar assistance. The solar panel won’t replace full charging but helps prolong battery life during outdoor activities – a reliable system Casio has long employed. Compared to Apple Watch Ultra 2 and Garmin Instinct 2 Solar, this is a more niche gadget aimed at surfers and G-Shock fans rather than users seeking a fully loaded smartwatch experience.
The sports and outdoor watch segment is expanding faster than traditional watch categories. According to Counterpoint Research, global smartwatch shipments maintain tens of millions per quarter, with brands increasingly targeting specialized niches like trail running, diving, and surfing. The GBX-H5600KI-5 fits firmly in this trend: it’s not a catch-all device for every notification but a dedicated tool for water-focused training and adventure.
Looking ahead, it will be interesting to see whether Casio can carve out a lasting slice of the competitive sports watch market by doubling down on durability and surf-centric features – areas where Apple and Garmin only offer partial support. If Casio expands these capabilities while preserving its iconic rugged design, it could attract a wider base of outdoor athletes who want more than just a smartwatch but less than a full activity wristband.