If you’re after raw performance, Xiaomi‘s newest flagship has plenty to offer.
The company has officially launched the REDMI K90 Ultra in China, packing flagship hardware, gaming-focused features, and one of the biggest batteries we’ve seen in a premium smartphone.
At the heart of the REDMI K90 Ultra is Qualcomm’s Snapdragon 8 Elite chipset, paired with Xiaomi’s D2 discrete graphics chip (also known as the Q3 gaming chip). It comes with LPDDR5X Ultra RAM and fast UFS 4.1 storage, with memory options of 12GB or 16GB and storage options of 256GB or 512GB.
Keeping all that power under control is a built-in active cooling fan. Xiaomi says it operates at just 32dB, making it quiet even under heavy loads. Surprisingly, the cooling fan itself is also rated IPX8 and IPX9 for dust and water resistance.
Battery life is another major highlight.
The REDMI K90 Ultra packs a huge 8,550mAh Xiaomi Jinshajiang battery, giving users more time for gaming, streaming, and everyday use.
Charging is equally impressive. The phone supports 100W wired fast charging and 22.5W wired reverse charging, allowing it to charge other compatible devices.
Xiaomi also added a direct power supply mode for gamers. Instead of drawing power from the battery while plugged in, the phone can power the motherboard directly. This helps reduce heat and minimizes battery wear during long gaming sessions.
The front of the phone is dominated by a 6.83-inch flat AMOLED display with a sharp 1.5K (2772 × 1280) resolution.
It uses Xiaomi’s M10 display panel and offers a super-smooth 165Hz refresh rate. The display also supports a 3,500Hz instant touch sampling rate for quicker touch response, HDR10+, Dolby Vision, DC Dimming, a minimum 5,000,000:1 contrast ratio, and up to 3,500 nits of peak brightness for better outdoor visibility.
For cameras, Xiaomi keeps things simple.
The REDMI K90 Ultra features a 50MP main camera using a 1/1.55-inch Light Fusion 800 sensor with an f/1.68 aperture. It also includes Optical Image Stabilization (OIS) and Electronic Image Stabilization (EIS), and supports recording videos in up to 8K resolution.
Joining it is an 8MP ultra-wide camera with an f/2.2 aperture.
On the front, there’s a 20MP selfie camera capable of recording videos at up to 1080p.
Gaming is clearly one of Xiaomi’s priorities with this phone.
The company worked with Tencent to improve the touch experience in popular games.
For Honor of Kings, players get customized “e-sports zone touch control” with optimizations for the movement joystick, skill buttons, and minimap.
For Peacekeeper Elite, Xiaomi added customized touch zones for movement, aiming, elimination, and other in-game actions.
The phone also comes with Bose-tuned 1115X symmetrical dual speakers for better audio, an 0815 X-axis linear motor for stronger vibration feedback, a 3D ultrasonic fingerprint scanner, and landscape network optimization to help maintain a stable connection while gaming.
Despite being built for performance, the REDMI K90 Ultra doesn’t skip durability.
It features an aluminum alloy CNC frame with an anodized finish and carries IP66, IP68, and IP69 ratings for dust and water resistance.
The phone measures 162.91 × 77.93 × 8.18mm, weighs 227g, and comes in Shadow Black, Space Silver, and Sky Blue.
It runs Xiaomi HyperOS 3 out of the box and supports Dual SIM, 5G SA/NSA, Dual 4G VoLTE, Wi-Fi 7, Bluetooth 5.4, NFC, USB Type-C, Hi-Res Audio, an infrared sensor, and support for Beidou, GPS, Galileo, GLONASS, QZSS, and NavIC navigation systems.
Pricing and availability
The REDMI K90 Ultra is already available in China.
The 12GB + 256GB variant is priced at 2,999 yuan (around US$441 / ₱25,600*).
The 16GB + 256GB model costs 3,199 yuan (around US$470 / ₱27,300*).
For those who need more storage, the 12GB + 512GB version is priced at 3,499 yuan (around US$515 / ₱29,900*).
Meanwhile, the top-end 16GB + 512GB variant retails for 3,699 yuan (around US$544 / ₱31,600*).
As part of its launch promo, Xiaomi is offering a 200 yuan discount on both 256GB variants during the first sale in China.