Compare / Redmi K90 Ultra vs 18 Fold
Redmi K90 Ultra vs 18 Fold
A side-by-side comparison of the Redmi K90 Ultra and the 18 Fold, covering display, chipset, memory, camera, battery and build.
Overview
Specifications
Redmi K90 Ultra
- Technology
- GSM / HSPA / LTE / 5G
- 2G bands
- GSM 850 / 900 / 1800
- 3G bands
- UMTS 2100 / 1700/2100 / 850 / 800 / 900 / 800 - HSUPA, HSUPA 5.8, HSDPA, HSPA+ 21.1, HSPA+ 42.2, DC-HSDPA 42.2
- 4G bands
- LTE bands 1, 3, 5, 7, 8, 19, 28, 34, 38, 39, 40, 41, 42, 48, 66 - 100/50, 150/50, 300/50, 300/75, 300/100, 450/50, 450/100, 600/50, 600/100
- 5G bands
- NR bands 1, 3, 5, 7, 8, 28, 38, 40, 41, 48, 66, 77, 78 - 1500, 2600, 3700 data links
- Dual SIM
- SIM2 supports same bands as SIM1
18 Fold
- Technology
- GSM / HSPA / LTE / 5G
- 2G bands
- GSM 850 / 900 / 1800 / 1900
- 3G bands
- HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100
- 4G bands
- 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 34, 38, 39, 40, 41, 42, 48, 66
- 5G bands
- 1, 2, 3, 5, 7, 8, 12, 13, 18, 20, 25, 26, 28, 34, 38, 39, 40, 41, 48, 66, 77, 78, 79 SA/NSA/Sub6
- Speed
- HSPA, LTE, 5G
Redmi K90 Ultra
- Announced
- 2026 Jun
- Status
- Available. Released 2026 Jun 29
18 Fold
- Announced
- 2026, September 07
- Status
- Available. Released 2026, September 07
Redmi K90 Ultra
- Dimensions
- 162.91 × 77.93 × 8.18 mm
- Weight
- 227 g
- Build
- Yes
- SIM
- Nano-SIM (4FF)
- Protection
- IP69 dust/water resistant (150 cm, 30 min)
- Extras
- Haptic touch feedback, Tactile touch feedback
18 Fold
- Dimensions
Unfolded: 163.8 x 117.8 x 5.0 mm
Folded: 83.6 x 117.8 x 10.7 mm
- Weight
- 219 g (7.72 oz)
- Build
- Glass front (Xiaomi Dragon Crystal Glass 3) (folded), plastic front (unfolded), glass back, aluminum frame
- SIM
Nano-SIM + Nano-SIM
IP58/IP59 dust protected and water resistant (high pressure water jets; immersible up to 1m for 30 min)
Redmi K90 Ultra
- Type
- AM-OLED display, 1073.7M colors, 165 Hz
- Size
- 6.8 inches
- Resolution
- 1280x2772 pixels (~447 PPI density), ~90.2% screen-to-body ratio
- Protection
- Yes
- Touch
- Capacitive multi-touch screen
- Notch/Hole
- 1-hole
18 Fold
- Type
- LTPO AMOLED120HzHDR10+Dolby VisionHDR Vivid4000 nits (peak)
- Size
- 7.58 inches, 174.8 cm2 (~90.6% screen-to-body ratio)
- Resolution
2364 x 1672 pixels (~382 ppi density)
Cover display:
LTPO AMOLED, 120Hz, Xiaomi Dragon Crystal Glass 3
5.38 inches, 1168 x 1712 pixels
HDR10+, Dolby Vision, HDR Vivid, 4000 nits (peak)
Redmi K90 Ultra
- OS
- Google Android 16 (Baklava)
- Chipset
- Qualcomm Snapdragon 8 Elite SM8750-AB (Sun) 3 nm
- CPU
- 4.32 GHz octa-core
- GPU
- Qualcomm Adreno 830 (1100 MHz)
18 Fold
- OS
- Android 17, HyperOS 4
- Chipset
- XRing O3 (3 nm)
- CPU
- 10-core 4.35 GHz
- GPU
- Arm G2-Ultra NX MC16
Redmi K90 Ultra
- Card slot
- No
- Internal
- 512GB 16GB RAM, 512GB 12GB RAM, 256GB 16GB RAM, 256GB 12GB RAM
- Interface
- UFS 4.1
18 Fold
- Card slot
- No
- Internal
256GB 12GB RAM, 512GB 12GB RAM, 512GB 16GB RAM, 1TB 16GB RAM
UFS 4.1
Redmi K90 Ultra
- Dual
50.1 MP, f/1.68, 24mm, 1.0 x optical zoom, BSI CMOS, 1.00µm, PD AF, EIS, EIS (video), OIS, Pixel unification, HDR photo, HDR video, Red-eye reduction, Slow motion video, Burst mode, Refocus, Touch focus, Macro mode, Panorama Photo, Face detection, Face tagging, Smile detection, Face retouch, Face retouch (video), Intelligent scene detection
8.0 MP, f/2.20, 15mm, (ultrawide), BSI CMOS, 1.12µm, HDR photo, HDR video, Slow motion video, Burst mode, Panorama Photo, Face detection, Face tagging, Smile detection, Face retouch, Face retouch (video), Intelligent scene detection
- Other features
- single LED flash
- Video
- 7680x4320 pixel
18 Fold
- Triple
200 MP, f/1.7, 23mm (wide), 1/1.56", 0.5µm, PDAF, OIS
50 MP, f/2.8, 80mm (telephoto), PDAF, OIS, 3.x optical zoom
50 MP, f/2.4, 17mm (ultrawide)
- Features
- Laser AFcolor spectrum sensorLeica lensesLED flashHDRpanorama
- Video
- 8K@24fps, 4K@30/60fps (Dolby Vision), 1080p@30/60/120/960fps, gyro-EIS, OIS
Redmi K90 Ultra
- Single
20.2 MP, f/2.00, BSI CMOS, Pixel unification, HDR photo, HDR video, Slow motion video, Burst mode, Panorama Photo, Face detection, Face tagging, Smile detection, Face retouch, Face retouch (video), Intelligent scene detection
- Video
- 1920x1080 pixel
18 Fold
- Single
16 MP, f/2.2, 21mm (wide)
Cover camera:
16 MP, f/2.2, 21mm (wide)
- Features
- HDR
- Video
- 1080p@30/60fps
Redmi K90 Ultra
- Loudspeaker
- 3
- 3.5mm jack
- No
- Audio features
- Voice speakerSpeakerphoneANCHD VoiceVoLTEViLTE
18 Fold
- Loudspeaker
- Yes, with stereo speakers, Dolby Atmos
- 3.5mm jack
No
24-bit/192kHz Hi-Res & Hi-Res wireless audio
Redmi K90 Ultra
- WLAN
- 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax, 802.11be
- Bluetooth
- Bluetooth 5.4
- Positioning
- Simultaneous GPSA-GPSDual-frequency GPSGeotaggingQuickGPSQZSSNavIC
- Satellite details
- GLONASS (L1OF); Galileo (E1, E5a); BeiDou (B1c, B1I, B2a BeiDou receiver)
- NFC
- Yes
- USB
- USB C reversible USB 2.0
- USB features
- USB chargingUSB fast chargingUSB HostUSB OTG 1.3USB OTG 2.0USB PDUSB PD 2.0USB PD 3.0
- Wireless features
- Miracast, Wi-Fi Direct, Wi-Fi Tethering, WiDi, Wi-Fi Calling
- IR
- Yes
18 Fold
- WLAN
- Wi-Fi 802.11 a/b/g/n/ac/6/7, dual-band
- Bluetooth
- 6.0, A2DP, LE, LHDC 5
- Positioning
- GPS (L1+L5)BDS (B1I+B1C+B1a)GALILEO (E1+E5a)QZSS (L1+L5)GLONASSNavIC
- NFC
- Yes
- Infrared port
- Yes
- Radio
- No
- USB
- USB Type-C 3.2 Gen2, OTG
Redmi K90 Ultra
- Sensors
- AccelerometerGyroCompassIn-screen FP sensorL sensorP sensorStep counterNFC
- Software
- Voice CommandBusiness card recognitionNavigation softwareAugmented Reality (AR)Intelligent personal assistantVoice RecognitionFace Recognition
18 Fold
- Sensors
Fingerprint (side-mounted), accelerometer, gyro, proximity, compass, barometer
Ultra Wideband (UWB) support
Redmi K90 Ultra
- Type
- 8550 mAh battery Li-ion (Si-C)
- Charging
- 100.0 W charging wired
18 Fold
- Type
- Si/C Li-Ion 6000 mAh
- Charging
67W wired, PD3.0, 50W PPS
50W wireless
Reverse wired
Redmi K90 Ultra
- Models
- Redmi K90 Ultra 5G Standard Edition Dual SIM TD-LTE CN 512GB M332BF
- Price
- ¥4,199
- Market
- Asia
- Countries
- China
18 Fold
- Colors
- Gray, Silver, Red, Rose gold
- Price
- About 1400 EUR (price in China)
How the Redmi K90 Ultra and 18 Fold differ
- The Redmi K90 Ultra has a larger battery, 8550 mAh against 6000 mAh on the 18 Fold.
- The 18 Fold has the bigger screen, 7.58 inches against 6.8 inches.
- The main cameras are 50.1 MP on the Redmi K90 Ultra and 200 MP on the 18 Fold.
- At launch the Redmi K90 Ultra was listed at $4,199 and the 18 Fold at $1,400 (USD).
- The 18 Fold is the newer of the two, released in August 2026.