LG X400 (K121S) vs Xiaomi 12S Ultra (256GB/12GB)
Side by side comparison between LG X400 vs Xiaomi 12S Ultra phones, differences, pros, cons and full specifications. What's the better?
,
5.3"
IPS
IPS
720x1280
13
MP
MP
5mp
2GB
RAM
RAM
Octa-core
2800
mAh
mAh
(Removable)
vs
6.73"
AMOLED
AMOLED
1440x3200
50
MP
MP
32mp
12GB
RAM
RAM
Octa-core
4860
mAh
mAh
(Non removable)
What's the better phone? Xiaomi 12S Ultra (256GB/12GB)
The phonemore's choice is much more technical than personal. Therefore, you shouldn't only consider this. Our goal is to help you, but what's important to us may not be important to you. You decide which one is the best! Comment!
8 Advantages 
34 Advantages | 15 Common items in both devices |
| Autofocus / LDAF/PDAF: laser/phase detection autofocus |
| Capacitive |
| Multitouch |
| Accelerometer |
| Ambient light sensor |
| Compass |
| Fingerprint sensor (rear-mounted) / Fingerprint sensor (under display) |
| +8 specs and more in the table below |
Check the comparison table below for more items that are not evaluated in comparison score above.
Highlight differences Clear highlight📱 Model features | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Model | X400 (K121S) | 12S Ultra (256GB/12GB) |
| Other model names | SKT LG X400, LGM-K121S, LGMK121S (SK Telecom) | 小米12S Ultra 5G (2203121C) 12GB RAM |
| Country or region available |  South Korea |  (Global, International) |
| Brand | LG | Xiaomi |
| Release date | 2/1/2017 | 7/9/2022, Announced: 7/4/2022 |
| Depth | 8 millimeters (0.31 inches) | 9 millimeters (0.35 inches) |
| Size (width x height) | 75.29 x 148.7 millimeters (2.96 x 5.85 in) | 74.97 x 163.17 millimeters (2.95 x 6.42 in) |
| Weight | 142 grams (4.97 ounces) | 225 grams (7.88 ounces) |
| Build, materials | Plastic body, glass front | Aluminum frame, glass front, leather back |
| Protection against water and others | Not supported | IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant |
📲 Display | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Display type | TFT IPS LCD | AMOLED |
| Screen size | 5.3" inches | 6.73" inches |
| Screen-to-body ratio | ~69.2% (screen-to-body ratio) | ~89.4% (screen-to-body ratio) |
| Display resolution | 720x1280 pixels | 1440x3200 pixels (20:9) |
| Touchscreen | Capacitive Multitouch | Capacitive Multitouch 10-points |
| Pixel density (dot pitch) | 277 PPI | 521 PPI |
| Colors | 16 million | 1 billion |
| Scratch-resistant glass | Not supported | Gorilla Glass Victus |
| Refresh rate | feature not registered | 120Hz |
| Display features | feature not registered | 1000nits[typ], 1500nits[peak] Dolby Vision/HDR10+ |
🤖 Operating System | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| System version | Android 7.0 Nougat | Android 12 |
| Firmware update | Android 8.0 Oreo | Android 13 |
| User Interface | feature not registered | MIUI 13 / 14 |
⚙️ Processor | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Chipset | 64bit: MediaTek MT6750 (28nm) | 64bit: Qualcomm Snapdragon 8+ Gen 1 (SM8475) (4nm) |
| CPU | Octa-core, 2 processors: 4x 1.5GHz ARM Cortex-A53 (Quad-core) 4x 1GHz ARM Cortex-A53 (Quad-core) | Octa-core, 3 processors: 1x 3.19GHz ARM Cortex-X2 (Single-core) 3x 2.75GHz ARM Cortex-A710 (Triple-core) 4x 2GHz ARM Cortex-A510 (Quad-core) |
| GPU graphical controller | ARM Mali-T860 MP2 520Mhz | Qualcomm Adreno 730 (818MHz) |
| Performance (benchmark) | feature not registered | AnTuTu: 1039412 (v9) Geekbench: 4300 (v5.1) GFXBench: 51fps (ES 3.1 onscreen) |
💽 Memory and storage | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| RAM memory | 2GB LPDDR3 | 12GB LPDDR5 |
| Internal storage | 32GB (22GB available) | 256GB (218GB available) UFS 3.1 |
| External storage | Until 256GB microSD, microSDXC (dedicated slot) | Not supported |
📶 Mobile networks | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Dual-SIM | Not supported | Dual-SIM Standby - Call active on one sim card |
| SIM card | 1 slot (Single-SIM) nano-SIM (4FF) | 2 slots (Dual-SIM) nano-SIM (4FF) |
| Maximum Download / Upload | 300/50 Mbps | 2000/1024 Mbps |
| Network technology | 2G, 3G, 4G | 2G, 3G, 4G, 5G |
| Frequency, bands | Expand band details Collapse details | |
| GSM MHz band | Tri-Band 900/1800/1900 | Quad-Band 850/900/1800/1900 |
| Primary 2G network | GSM 900/1800/1900 | CDMA 800, GSM 850/900/1800/1900 |
| Primary 3G network | UMTS 2100 | CDMA2000 1xEV-DO UMTS 800/850/900/1700/1900/2100 |
| Primary 4G network | LTE Cat6 850/900/1800/2100/2600 (Bands 1,3,5,7,8) VoLTE | LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 17, 18, 19, 26) TD-LTE (34, 38, 39, 40, 41, 42) VoLTE |
| Primary 5G network | Not supported | SA/NSA (1, 3, 5, 8, 28, 38, 40, 41, 77, 78, 79) |
| Primary data network | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, LTE, LTE-A | GPRS, EDGE, CDMA2000 EV-DO Rev 0, CDMA2000 EV-DO Rev A, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA |
| Secondary 2G network | Not supported | GSM 850/900/1800/1900 |
| Secondary 3G network | Not supported | UMTS 800/850/900/1700/1900/2100 |
| Secondary 4G network | Not supported | LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 17, 18, 19, 26) TD-LTE (34, 38, 39, 40, 41, 42) VoLTE |
| Secondary data network | Not supported | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA |
📷 Camera | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Back camera (main camera) | 13 megapixels | (quad camera) 50 megapixels 48MP periscope telephoto f/4.1120mm1/2"0.8µmPDAFOIS5x-optical-zoom 48MP ultrawide f/2.213mm128°1/2"0.8µmDual-PixelPDAF 0.3MP TOF 3D depth |
| Main camera resolution | 4160x3120 pixels | 8160x6120 pixels |
| Video recording (primary) | Full HD (1920x1080) 30 fps | 8K UHD (7680x4320) 24 fps |
| Flash | LED flash | Dual-LED flash |
| Focal aperture | f/2.2 (aperture) | f/1.9 (aperture) |
| Focal length | feature not registered | 23mm (lens) |
| Sensor size | 1/3" inches | 1/1" inches |
| Pixel size | 1.12µm pixel | 1.6µm pixel |
| Autofocus | Autofocus | LDAF/PDAF: laser/phase detection autofocus |
| Touch focus | Supported | Supported |
| Image stabilization | EIS: Digital stabilization | OIS: Optical stabilization |
| Zoom | Only digital zoom | Digital and optical zoom |
| Face/smile detection | Face detection, Smile detection | Face detection, Smile detection |
| BSI sensor | Not supported | Supported |
| HDR | HDR photo only main camera | HDR photo/video on both cameras |
| Camera extras | feature not registered | 4K@60fps 1080p@480fps Sony IMX989 Leica optics |
📸 Front camera | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Front camera (secondary) | 5 megapixels | 32 megapixels |
| Front camera resolution | 2560x1920 pixels | 6528x4896 pixels |
| Video recording (secondary) | Full HD (1920x1080) | 4K UHD (3840x2160) |
| Front flash | Not supported | Not supported |
| Focal aperture | f/2.4 (aperture) | f/2.4 (aperture) |
| Focal length | feature not registered | 25mm (lens) |
| Sensor size | 1/5" inches | feature not registered |
| Pixel size | 1.12µm pixel | 0.7µm pixel |
🔉 Sound and multimedia | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Loudspeaker | Supported | Stereo sound 24-bit/192kHz Tuned by Harman Kardon |
| Active noise cancellation | 2 microphones or more | 2 microphones or more |
| Radio | FM (RDS) | Not supported |
| TV | Digital TV | Not supported |
| Video formats | MP4, H.264, H.263, XviD, MKV | MP4, H.265, H.264, H.263, XviD, MKV |
| Audio formats | MP3, WAV, WMA, eAAC+, FLAC | MP3, WAV, WMA, eAAC+, FLAC |
🔌 Connectivity | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| USB | MicroUSB 2.0, USB OTG On-The-Go | USB 2.0 Type-C, USB OTG On-The-Go |
| Audio output | 3.5mm jack | Type-C reversible connector |
| TV output | Not supported | USB Type-C (reversible) |
| Bluetooth | 4.2 + A2DP | 5.2 + A2DP/LE |
| WiFi | 802.11 b/g/n [wifi4] (2.4GHz) WiFi Direct, hotspot | 802.11 a/b/g/n/ac/ax [wifi6E/6] (2.4GHz, 5GHz, 6GHz) + MIMO WiFi Direct, hotspot |
| DLNA | Not supported | Supported |
| GPS | A-GPS, GeoTagging, GLONASS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou, QZSS, NavIC |
| NFC | Supported | Supported |
| Infrared port | Not supported | Supported |
🧭 Sensors | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Sensors | Accelerometer Ambient light sensor Compass Fingerprint sensor (rear-mounted) Proximity sensor | Accelerometer Ambient light sensor Barometer Compass Face unlock 2D Fingerprint sensor (under display) Gyroscope Virtual proximity sensor |
| Vibrating alert | Supported | Supported |
🔋 Battery | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Battery type | Li-Ion: lithium-ion (Removable) | LiPo: li-ion polymer (Non removable) |
| Battery capacity | 2800 mAh | 4860 mAh |
| Charger, watts | Wired charging | 67W Wired fast charging Reverse charging by cable Quick Charge 4 USB Power Delivery 3.0 |
| Inductive / wireless charging | feature not registered | 50W Qi wireless charging 10W Reverse wireless charging |
| Talk time autonomy | 9 hours | feature not registered |
| Standby | 390 hours (16.3 days) | feature not registered |
➕ Other features | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| Call control | Voice dialing, Voice recorder | Voice dialing, Voice recorder, Voice commands |
| Messaging | SMS (T9), MMS, E-mail, Push mail | SMS (T9), MMS, E-mail, Push mail |
| Hands-free calling | Supported | Supported |
| Video calling | Supported | Supported |
| Ringtones | Polyphonic and customized | Polyphonic and customized |
| Web browser | HTML, XHTML, HTML5 | HTML, XHTML, HTML5 |
| Antenna | Internal antenna | Internal antenna |
| Qwerty physical keyboard | Not supported | Not supported |
| Miscellaneous | • Colors: Black, Gold • 2.5D Arc Glass screen • LG UX 5.0 • Wide-angle 120° front camera • KnockOn, Knock Code • DMB-TV (Korea) | • Colors: Black, Dark Green |
☢️ Radiation rate | ||
| LG X400 (K121S) | Xiaomi 12S Ultra (256GB/12GB) | |
| SAR 1.6W/kg (USA, Mexico, etc.) | feature not registered | feature not registered |
| SAR 2W/kg (Europe, UK, etc.) | feature not registered | feature not registered |