Side-by-side technical data
Xiaomi Redmi K90 Ultra vs Xiaomi Redmi 8
Comparison between Xiaomi Redmi K90 Ultra and Xiaomi Redmi 8: camera, battery, fast charging, display, performance and colors, side by side. More phones from Xiaomi.
NeoTeo's verdict
Which of the two is the better buy
The Xiaomi Redmi K90 Ultra is the pick for a smoother display and far stronger performance; the Redmi 8 makes sense only if it costs less. The move from AMOLED to IPS LCD and from 165 Hz to 60 Hz sets them apart at a glance.
The K90 Ultra has a 6.83″ display at 1280 px × 2772 px and 447 ppi; the Redmi 8 has a 6.22″ panel at 720 px × 1520 px and 270 ppi. A Snapdragon 8 Elite, 16 GB of RAM, and UFS 4.1 put it well ahead of the Snapdragon 439, 4 GB of RAM, and eMMC 5.1. The Redmi 8 is lighter at 188 g, versus 227 g.
There is a wide gap in cameras and battery, too. The K90 Ultra's main camera is 50 MP versus 12 MP, and it adds an ultrawide camera; the Redmi 8 records video up to 1080p at 30 fps. The K90 Ultra pairs an 8550 mAh battery with 100 W charging, while the Redmi 8 has 5000 mAh and 18 W charging. The K90 Ultra also brings 5G, NFC, and Android 16; the Redmi 8 has 4G, a 3.5 mm audio jack, and Android 9.
Xiaomi Redmi K90 Ultra
The Xiaomi Redmi K90 Ultra suits buyers who want a 165 Hz AMOLED display and a Snapdragon 8 Elite with 16 GB of RAM.
Xiaomi Redmi 8
The Xiaomi Redmi 8 is the better buy only if it costs less: at 188 g it is lighter than the K90 Ultra's 227 g, but that does not offset its drawbacks.
The verdict
Your pick: Xiaomi Redmi K90 Ultra, ahead on Design & display, Performance & hardware, Camera, Connectivity and Battery & charging.
| Category | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Design & display | 8.6 | 4.5 |
| Performance & hardware | 9.1 | 2.5 |
| Camera | 7.4 | 3.6 |
| Connectivity | 7.9 | 3.9 |
| Battery & charging | 8.3 | 5.4 |
Which one is for you?
Xiaomi Redmi K90 Ultra, if you care about…
- Battery Capacity
- 8,550 mAh
- against 5,000 mAh
- RAM Capacity
- 16 GB
- against 4 GB
- Wi-Fi Standards
- Wi-Fi 4 (802.11n), Wi-Fi 5 (802.11ac), Wi-Fi 6 (802.11ax), Wi-Fi 7 (802.11be), Wi-Fi 802.11a/b/g
- against Wi-Fi 802.11 b/g/n, Wi-Fi 4 (802.11n)
- Storage Type
- UFS 4.1
- against eMMC 5.1
Xiaomi Redmi 8, if you care about…
- Weight
- 188 g
- against 227 g
Specification comparison
Performance
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Processor Model | Qualcomm Snapdragon 8 Elite | Qualcomm Snapdragon 439 |
| Processor Process Size | 3 nm Best value | 12 nm |
| Graphics GPU | Qualcomm Adreno 830 | Qualcomm Adreno 505 |
| Storage Type | UFS 4.1 Best value | eMMC 5.1 |
| Maximum CPU Clock | 4.32 GHz Best value | 1.95 GHz |
| Maximum Storage Capacity | 1 TB Best value | 64 GB |
| AnTuTu Score | 3,081,184 | 89,903 |
| Geekbench 6 Single-Core | 3,234 Best value | 492 |
| Geekbench 6 Multi-Core | 10,059 Best value | 1,701 |
| CPU Description | Octa-core CPU with 2x4.32 GHz and 6x3.53 GHz cores | Octa-core CPU with 4 Cortex-A53 cores at 1.95 GHz and 4 Cortex-A53 cores at 1.45 GHz. |
| Processor Type | Octa-Core | Octa-Core |
| 64-Bit Processor | Yes | Yes |
| RAM Capacity | 16 GB Best value | 4 GB |
| RAM Type | LPDDR5X Best value | DDR3 |
| AnTuTu version | v11 | — |
Design
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Body Colors | Black, Blue, Silver | Black, Red, Blue |
| Body Thickness | 8.2 mm Best value | 9.4 mm |
| Body Width | 77.9 mm | 75.4 mm |
| Body Height | 162.9 mm | 156.5 mm |
| Weight | 227 g | 188 g Best value |
| Usable Surface | 90.3 % Best value | 81.8 % |
| Body Materials | Glass, Aluminium Alloy Best value | Glass, Plastic |
| Resistance Features | IP68, IP69, IP66 | Water Resistant |
| Waterproof Depth | 1.5 m | — |
Battery
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Battery Capacity | 8,550 mAh Best value | 5,000 mAh |
| Battery Type | Si-Carbon Li-Ion Best value | Li-Polymer |
| Fast Charge Power | 100 W Best value | 18 W |
| Battery Features | Non-Removable, Fast Charging, Reverse Charging, Reverse Wireless Charging, Rechargeable, Battery Level Indicator Best value | Fast Charging, Battery Level Indicator, Rechargeable |
| Reverse wireless charging power | 22.5 W | — |
Display
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Display Aspect Ratio | 19.5:9 | 19:9 |
| Display Technology | AMOLED Best value | IPS LCD |
| Peak Display Brightness | 9,500 nits Best value | 400 nits |
| Display Diagonal | 6.83″ Best value | 6.22″ |
| Display Horizontal Resolution | 1,280 px Best value | 720 px |
| Display Vertical Resolution | 2,772 px Best value | 1,520 px |
| Display Pixel Density | 447 ppi Best value | 270 ppi |
| Display Refresh Rate | 165 Hz Best value | 60 Hz |
| Touch Sampling Rate | 480 Hz | — |
| Display Contrast Ratio | 8,000,000 :1 | — |
| Display Features | Hole-Punch Notch, HDR10, HDR10+, Dolby Vision, Always-On Display, Capacitive Touch, Multi-Touch, Gorilla Glass, DC Dimming, DCI-P3, TÜV Rheinland Low Blue Light, TÜV Rheinland Flicker-Free Certified, TÜV Rheinland Eye Comfort Certification, Scratch Resistant, Frameless | Gorilla Glass 5, IPS LCD, Touchscreen |
Sensors
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Fingerprint Sensor Placement | Under Display | Rear |
Sensor
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Sensor Features | Fingerprint Sensor, Accelerometer, Proximity Sensor, Gyroscope, Compass, Hall Sensor, Light Sensor, RGB Sensor, Cooling System | Fingerprint Sensor, Accelerometer, Proximity Sensor, Compass |
Software
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Operating System | Android 16 | Android 9 |
| OS Family | Android | Android |
| OS Version | 16 Best value | 9 |
Connectivity
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| SIM Configurations | Dual Nano-SIM, Dual SIM Dual Standby | Dual Nano-SIM |
| Cellular Bands | 2G GSM 850, 2G GSM 900, 2G GSM 1800, 2G GSM 1900, 3G UMTS B1, 3G UMTS B2, 3G UMTS B3, 3G UMTS B4, 3G UMTS B5, 3G UMTS B6, 3G UMTS B8, 3G UMTS B19, 4G LTE B1, 4G LTE B3, 4G LTE B4, 4G LTE B5, 4G LTE B7, 4G LTE B8, 4G LTE B19, 4G LTE B28A, 4G LTE B34, 4G LTE B38, 4G LTE B39, 4G LTE B40, 4G LTE B41, 4G LTE B42, 4G LTE B48, 4G LTE B66, 5G NR n1, 5G NR n3, 5G NR n5, 5G NR n7, 5G NR n8, 5G NR n28a, 5G NR n38, 5G NR n40, 5G NR n41, 5G NR n48, 5G NR n66, 5G NR n77, 5G NR n78 | 2G GSM 850, 2G GSM 900, 2G GSM 1800, 2G GSM 1900, 3G UMTS B850, 3G UMTS B900, 3G UMTS 1700 AWS, 3G UMTS 1900, 3G UMTS 2100, 4G LTE B1, 4G LTE B2, 4G LTE B3, 4G LTE B4, 4G LTE B5, 4G LTE B7, 4G LTE B8, 4G LTE B20, 4G LTE B38, 4G LTE B40 |
| Cellular Technologies | GSM, HSPA, LTE, 5G Best value | GSM, HSPA, UMTS, LTE, 4G |
| Wi-Fi Standards | Wi-Fi 4 (802.11n), Wi-Fi 5 (802.11ac), Wi-Fi 6 (802.11ax), Wi-Fi 7 (802.11be), Wi-Fi 802.11a/b/g Best value | Wi-Fi 802.11 b/g/n, Wi-Fi 4 (802.11n) |
| Wi-Fi Features | Dual Band, Wi-Fi Hotspot, Wi-Fi Direct, Wi-Fi Display, MIMO | Wi-Fi Direct, Wi-Fi 802.11 b/g/n |
| Bluetooth Version | Bluetooth 5.4 Best value | Bluetooth 4.2 |
| Bluetooth Profiles | A2DP, LE, LHDC 5.0, ASHA, Auracast | A2DP, LE |
| Navigation Systems | GPS, A-GPS, GLONASS, BeiDou, Galileo, QZSS, NavIC Best value | GPS, GLONASS, Galileo, BeiDou |
| Connectivity Features | USB Charging, USB Mass Storage, USB OTG, USB Type-C, NFC, Computer Sync, OTA Sync, Tethering, Infrared, VoLTE | 3.5 mm Audio Jack, Infrared, FM Radio, USB Type-C, USB OTG, USB Charging |
| USB Version | USB 3.2 Best value | USB 2.0 |
| SAR American Head | — | 0.34 W/kg |
| SAR American Body | — | 1 W/kg |
| SAR (EU) head | — | 0.23 W/kg |
| SAR (EU) body | — | 1.48 W/kg |
| Max. download speed | 10,000 Mbps Best value | 150 Mbps |
| Max. upload speed | 3,500 Mbps Best value | 75 Mbps |
Audio
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Microphone Count | — | 2 |
| Audio Features | Stereo Speakers, Dolby Atmos, Hi-Res Audio, Hi-Res Wireless Audio, A2DP, LE, LHDC 5, ASHA, Auracast Best value | A2DP, LE, Loudspeaker |
Technical
| Specification | Redmi K90 Ultra | Redmi 8 |
|---|---|---|
| Model numbers | 2604FRK1EC | M1908C3IC, MZB8255IN, M1908C3IG, M1908C3IH |
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