The Xiaomi Redmi K90 refuses to choose between power and endurance. It’s a device that was, quite literally, cold-carved into existence, offering the tactile experience of holding polished art. But beneath that seamless, integrated glass lies the unrelenting heart of a desktop PC, coupled with an almost defiant dedication to endurance. This phone ensures that the charging indicator is the last thing you’ll ever worry about.
Design: Sculpted Glass and the Golden Size
Premium Build, Pure Look
I’ve been looking at the construction details, and honestly, they didn’t cut corners here. Xiaomi has focused heavily on texture and integration.
The back uses a single piece of 2mm thick glass, shaped by an intricate Integrated Cold Carving Process. This process involved 12 cutting tools, 41 process steps, and three rounds of CNC carving.
This detailed construction leads to a smooth as silk transition between the back cover and the camera area, which is specifically designed to be dust-proof.
The final look is enhanced by the light-mist integrated cold carving solution, a four-micro-curved middle frame, and more rounded corners.
Color Options
You can get the Redmi K90 in four colors: Black, White, Aquamarine, and Light Purple. These options complement the phone’s high-end integrated design.
Ergonomics and Durability
Considering the 7100mAh battery, I was expecting a brick, but the dimensions are quite well balanced. It measures 157.5 x 75.3 mm, is 8.0mm thick, and weighs 206g.
Xiaomi refers to the 6.59-inch size as the Golden Size, suggesting it offers a good balance between comfortable one-handed operation and an immersive experience.
The phone has an IP68 Dust and Water Resistance rating, which is the gold standard for protection against immersion.
Display: The Super Pixel Eye Care Screen
Clarity, Color, and Extreme Brightness
Let’s be direct: the Xiaomi Redmi K90 display specs look truly compelling. This 6.59-inch OLED Flat Screen features a Super Pixel resolution of 2510×1156. The key upgrade is the All-RGB lossless arrangement, which makes text and line edges clearer and provides colors that are more accurate compared to traditional display arrangements.
The screen offers impressive brightness, supporting up to 3500 nits Multi-Scene Peak Brightness thanks to the new M10 New Generation Luminous Material. This new material uses a red luminous compound that improves luminous efficiency and reduces power consumption.
The display supports 12bit Color Depth (68.7 billion colors) and advanced features like Full Brightness DC Dimming, Professional Primary Color Screen, and Multi-Screen Color Consistency. It also includes technologies like HDR10+, HDR Vivid, and Dolby Vision.
Eye Protection and Responsiveness
For me, one of the most reassuring aspects of the Redmi K90 is the clear commitment to Eye Care. The All-RGB arrangement is specifically designed to place less burden on your eyes, aiming to make long reading or video sessions less tiring. The screen supports an Extreme Low Light Environment minimum of just 1nit, and works with Circadian Rhythm Eye Care and Blue Light Filtering to reduce flicker.
For interaction, you get a smooth 120Hz Display Frame Rate and a quick 480Hz Touch Sampling Rate.
Performance: Desktop-Level Architecture
The Snapdragon 8 Elite Engine
If I had to sum up the Xiaomi Redmi K90 in one thought, it would be a phone designed not to back down from any challenge. It uses the Qualcomm Snapdragon 8 Elite chipset, built on TSMC’s 3nm process technology. This cutting-edge architecture features dual ultra-large cores with a main frequency up to 4.32GHz. This high performance is what allows REDMI to make the claim of power that rivals a PC desktop. The graphical horsepower is supplied by the Adreno 830 GPU.
Cooling and Dynamic Management
To manage this considerable power output, the phone uses REDMI’s First Three-Stage Raised Ice-Sealed Cooling. This system features a large 5300mm² LHP (Liquid Heat Pipe) and a gas-liquid separation channel design, intended to keep the core temperature low even under maximum load.
Performance is further optimized by a suite of software features: CPU/SLC Storage Dynamic Management, the Adaptive Performance Engine, and the all-new Mad Engine, which aims to save frame drops during heavy use.
Configurations and Storage
The memory options are flexible and high-end, ranging from 12GB up to 16GB of RAM. Storage is extensive, starting at 256GB and extending up to a maximum of 1TB of storage, offering you the highest option of 16GB RAM + 1TB storage.
Camera & Audio: Imaging and Acoustic Heritage
Flagship Triple Camera System
When I look at the sensor data, I see the Redmi K90 camera is anchored by the idea of Lossless Five Focal Lengths. The main camera is a 50MP unit using the Light Hunter™ 800 High Dynamic Sensor (1/1.55″ sensor, f/1.88 aperture). It features Optical Image Stabilization and a 6P Lens. The sensor uses 4-in-1 2.0μm Fusion Pixel technology for improved low-light performance. The system also supports a dedicated 2.5X Golden Telephoto Portrait mode.
Advanced Photography Modes and Video
Video capabilities include support for up to 8K video at 30FPS and 4K at 60FPS. For advanced motion capture, you can record Slow Motion up to 960FPS at both 1080p and 720p resolutions.
The camera software suite offers various modes, including Sports Capture, Night Scene, Super Stabilization, ID Photocopy Mode, and Long Exposure.
The High-Resolution Selfie Camera
The front camera is a high-resolution 20MP HD Portrait Camera packed with practical features like Fill Light, Video Beautify, and a useful Teleprompter mode for recording.
Sound by Bose
The audio collaboration is noteworthy. REDMI has merged its computing power with Bose’s acoustic heritage and Sound by Bose technology. The result is a promise of a high-quality acoustic experience with full bass and rich details.
The Super Linear Symmetrical Stereo Dual Speakers (1115F) are designed to create distinct sound layers. The audio experience is certified with Hi-Res and Hi-Res Audio Wireless, Dolby Atmos, and QQ Music Premium Sound Quality.
Endurance & Charging: The 7100mAh Core
Battery Capacity
This is one of the phone’s most vital features. Thanks to Advanced packaging and high-density stacking technology, the slim body accommodates a 7100mAh Xiaomi Jinshajiang Battery. This huge capacity is designed to alleviate common battery anxiety. The top-tier model in this series, the Redmi K90 Pro Max, packs an even larger capacity.
Intelligent and Versatile Charging
The phone supports 100W Wired Fast Charging, managed by the newly upgraded Xiaomi Surge P3 Smart Fast Charging Chip and the G1 Battery Management Chip, which improves efficiency. Charging protocols supported are extensive, including QC2.0/3.0/3+ and PD2.0/3.0.
The included charger is a standard 100W GaN Charger that is compatible with the PD charging protocol. For additional utility, it supports 22.5W Wired Reverse Charging, allowing your smartphone to function as a power bank. Note that the 100W PPS function will be gradually pushed out via OTA starting mid-November 2025.
Connectivity & Quality of Life: Security and OS
Security and Practicality
For access, the phone features a 3D Ultrasonic Fingerprint sensor and, notably, Wet Hand Touch capability, so you can reliably use the screen and unlock the phone even with damp hands.
Connectivity includes NFC and dual Nano-SIM card slots with 5G residency for all carriers.
Software Platform
The phone runs on the new Xiaomi HyperOS 3 operating system, which is based on Android 16.
In the Box: What You Get
I always appreciate a company that gives you everything you need right away, and Xiaomi hasn’t skimped here. You get the Redmi K90 Phone, plus the essential 100W Power Adapter and the USB Type-C Data Cable. Crucially, they include a Phone Case and a Screen Protective (pre-applied), so you don’t have to scramble for protection on day one. A SIM Eject Tool and the Instruction Manual round out the package.
Conclusion: My first look at the Redmi K90
The Xiaomi Redmi K90 is positioned as a serious competitor in the mid-range market. This phone is clearly engineered to maximize value for the buyer who wants high-end features without paying a premium. I see a device that firmly challenges the middle of the market by borrowing heavily from true flagships.
The combination of the 3nm Snapdragon 8 Elite processor, the advanced cooling system, and the huge 7100mAh battery provides a performance and endurance package that feels far above its class. Added features like the ultra-bright 3500-nit Super Pixel Eye Care Screen, the robust IP68 rating, and the high-quality Sound by Bose acoustic system cement its reputation as a serious contender. If you are looking for a highly capable phone that delivers top-shelf features at a competitive point, the Redmi K90 is definitely worth your serious consideration.
