Side-by-side technical data
Xiaomi Redmi K90 Ultra vs Xiaomi Redmi 15 4G
Comparison between Xiaomi Redmi K90 Ultra and Xiaomi Redmi 15 4G: 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 choice for anyone seeking the more complete phone: it clearly leads the Redmi 15 4G in performance, display, cameras, battery and connectivity. The Redmi 15 4G is the better buy only if it costs less, although it adds expandable storage and Google services.
The clearest difference is the display: AMOLED at 9,500 nits, 165 Hz and 447 ppi on the K90 Ultra versus IPS LCD at 700 nits, 144 Hz and 374 ppi on the Redmi 15 4G. The K90 Ultra also has 90.3% usable surface versus 83.2%, plus IP68, IP69 and IP66 protection rather than IP64.
For games and demanding tasks, the K90 Ultra combines a Snapdragon 8 Elite, 16GB of RAM, UFS 4.1 and an AnTuTu score of 3,081,184; the Redmi 15 4G has a Snapdragon 685, 8GB, UFS 2.2 and 338,000. Their main cameras use 1.13 µm pixels and f/1.7 versus 0.64 µm and f/1.8, with optical stabilization and an ultrawide camera only on the K90 Ultra. Its battery is 8,550 mAh with 100W charging, versus 7,000 mAh and 33W; both reach 62 hours per cycle.
Xiaomi Redmi K90 Ultra
The Xiaomi Redmi K90 Ultra is better for anyone seeking top performance, an AMOLED display and 100W charging.
Xiaomi Redmi 15 4G
The Redmi 15 4G is the better buy only if it costs less; its advantages are expandable storage and Google services.
The verdict
Your pick: Xiaomi Redmi K90 Ultra, ahead on Design & display, Performance & hardware, Camera, Connectivity and Battery & charging.
| Category | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Design & display | 8.6 | 5.9 |
| Performance & hardware | 9.1 | 4.9 |
| Camera | 7.4 | 3.8 |
| Connectivity | 7.9 | 5.8 |
| Battery & charging | 8.3 | 6.3 |
Which one is for you?
Xiaomi Redmi K90 Ultra, if you care about…
- Battery Capacity
- 8,550 mAh
- against 7,000 mAh
- AnTuTu Score
- 3,081,184
- against 338,000
- RAM Capacity
- 16 GB
- against 8 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 4 (802.11n), Wi-Fi 5 (802.11ac), Wi-Fi 802.11a/b/g
Xiaomi Redmi 15 4G, if you care about…
- Expandable Storage
- Yes
- against No
- Google Services
- Yes
- against No
Specification comparison
Performance
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Processor Model | Qualcomm Snapdragon 8 Elite | Qualcomm Snapdragon 685 |
| Processor Process Size | 3 nm Best value | 6 nm |
| Graphics GPU | Qualcomm Adreno 830 | Qualcomm Adreno 610 |
| Storage Type | UFS 4.1 Best value | UFS 2.2 |
| Maximum CPU Clock | 4.32 GHz Best value | 2.8 GHz |
| Maximum Storage Capacity | 1 TB Best value | 256 GB |
| AnTuTu Score | 3,081,184 Best value | 338,000 |
| Geekbench 6 Single-Core | 3,234 Best value | 473 |
| Geekbench 6 Multi-Core | 10,059 Best value | 1,510 |
| CPU Description | Octa-core CPU with 2x4.32 GHz and 6x3.53 GHz cores | Octa-core CPU with 4 Cortex-A73 cores at 2.8 GHz and 4 Cortex-A53 cores at 1.9 GHz. |
| Processor Type | Octa-Core | Octa-Core |
| 64-Bit Processor | Yes | Yes |
| RAM Capacity | 16 GB Best value | 8 GB |
| RAM Type | LPDDR5X Best value | LPDDR4X |
| Expandable Storage | No | Yes Best value |
| AnTuTu version | v11 | v10 |
Design
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Body Colors | Black, Blue, Silver | Black, Grey, Purple, Blue, Silver |
| Body Thickness | 8.2 mm Best value | 8.6 mm |
| Body Width | 77.9 mm | 82.1 mm |
| Body Height | 162.9 mm | 171.1 mm |
| Weight | 227 g | 224 g Best value |
| Usable Surface | 90.3 % Best value | 83.2 % |
| Body Materials | Glass, Aluminium Alloy Best value | Plastic |
| Resistance Features | IP68, IP69, IP66 Best value | IP64 |
| Waterproof Depth | 1.5 m | — |
| Drop Resistance Class | — | A |
| Repairability Class | — | C |
| Drop Test Count | — | 270 |
Battery
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Battery Efficiency Rating | — | B |
| Battery Capacity | 8,550 mAh Best value | 7,000 mAh |
| Battery Type | Si-Carbon Li-Ion | Si-Carbon Li-Ion |
| Fast Charge Power | 100 W Best value | 33 W |
| Battery Features | Non-Removable, Fast Charging, Reverse Charging, Reverse Wireless Charging, Rechargeable, Battery Level Indicator Best value | Fast Charging, Non-Removable, Battery Level Indicator, Charger Included, Rechargeable |
| Battery Endurance | — | 62 h |
| Charge cycles | — | 1,000 |
| Reverse wireless charging power | 22.5 W Best value | 18 W |
Display
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Display Aspect Ratio | 19.5:9 | 19.5:9 |
| Display Technology | AMOLED Best value | IPS LCD |
| Peak Display Brightness | 9,500 nits Best value | 700 nits |
| Display Diagonal | 6.83″ | 6.9″ Best value |
| Display Horizontal Resolution | 1,280 px Best value | 1,080 px |
| Display Vertical Resolution | 2,772 px Best value | 2,340 px |
| Display Pixel Density | 447 ppi Best value | 374 ppi |
| Display Refresh Rate | 165 Hz Best value | 144 Hz |
| Touch Sampling Rate | 480 Hz Best value | 288 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 | Hole-Punch Notch, Mohs Level 6, TÜV Rheinland Low Blue Light, TÜV Rheinland Flicker-Free Certified, TÜV Rheinland Eye Comfort Certification, DCI-P3, Scratch Resistant, Capacitive Touch, Multi-Touch, Frameless |
Sensors
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Fingerprint Sensor Placement | Under Display | Side |
Sensor
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Sensor Features | Fingerprint Sensor, Accelerometer, Proximity Sensor, Gyroscope, Compass, Hall Sensor, Light Sensor, RGB Sensor, Cooling System | Fingerprint Sensor, Accelerometer, Compass, Gyroscope, Light Sensor, Virtual Proximity Sensing, Cooling System |
Software
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Operating System | Android 16 | Android 15 |
| OS Family | Android | Android |
| OS Version | 16 Best value | 15 |
| OS Update Support | — | 5 years |
| Google Services | No | Yes Best value |
Connectivity
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| SIM Configurations | Dual Nano-SIM, Dual SIM Dual Standby | Dual Nano-SIM, Dual SIM Dual Standby |
| 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 B1, 3G UMTS B5, 3G UMTS B8, 3G UMTS B6, 3G UMTS B7, 3G UMTS B9, 3G UMTS B10, 3G UMTS B11, 3G UMTS B12, 3G UMTS B13, 3G UMTS B17, 3G UMTS B20, 3G UMTS B21, 3G UMTS B28A, 3G UMTS B28B, 3G UMTS B32, 3G UMTS B38, 3G UMTS B40, 3G UMTS B41, 3G UMTS B42, 3G UMTS B43, 3G UMTS B48, 3G UMTS B66, 3G UMTS B77, 3G UMTS B78, 4G LTE B1, 4G LTE B3, 4G LTE B5, 4G LTE B7, 4G LTE B8, 4G LTE B20, 4G LTE B28A, 4G LTE B28B, 4G LTE B38, 4G LTE B40, 4G LTE B41, 4G LTE B2, 4G LTE B4 |
| Cellular Technologies | GSM, HSPA, LTE, 5G Best value | GSM, HSPA, LTE |
| 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 4 (802.11n), Wi-Fi 5 (802.11ac), Wi-Fi 802.11a/b/g |
| Wi-Fi Features | Dual Band, Wi-Fi Hotspot, Wi-Fi Direct, Wi-Fi Display, MIMO | Dual Band, Wi-Fi Hotspot, Wi-Fi Direct, Wi-Fi Display |
| Bluetooth Version | Bluetooth 5.4 Best value | Bluetooth 5.0 |
| Bluetooth Profiles | A2DP, LE, LHDC 5.0, ASHA, Auracast | A2DP, LE |
| Navigation Systems | GPS, A-GPS, GLONASS, BeiDou, Galileo, QZSS, NavIC Best value | GPS, A-GPS, GLONASS, BeiDou, Galileo |
| Connectivity Features | USB Charging, USB Mass Storage, USB OTG, USB Type-C, NFC, Computer Sync, OTA Sync, Tethering, Infrared, VoLTE | Virtual Proximity Sensing, Infrared, NFC, USB Type-C, Computer Sync, Tethering, VoLTE, USB Charging, USB Mass Storage, USB Host 2.0, USB OTG, USB 2.0 |
| USB Version | USB 3.2 Best value | USB 2.0 |
| Max. download speed | 10,000 Mbps Best value | 390 Mbps |
| Max. upload speed | 3,500 Mbps Best value | 150 Mbps |
Audio
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Audio Features | Stereo Speakers, Dolby Atmos, Hi-Res Audio, Hi-Res Wireless Audio, A2DP, LE, LHDC 5, ASHA, Auracast | Stereo Speakers, Dolby Atmos, A2DP, LE |
Technical
| Specification | Redmi K90 Ultra | Redmi 15 4G |
|---|---|---|
| Model numbers | 2604FRK1EC | 24129PN74G, 25062RN2DE, 25062RN2DA |
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