Product
Xiaomi Redmi 9
Xiaomi Redmi 9
Samsung Z4
Samsung Z4
Battery
Charging 18W wired -
Type Li-Po 5020 mAh Li-Ion 2050 mAh, removable
Body
Build Glass front (Gorilla Glass 3), plastic back, plastic frame -
Dimensions 163.3 x 77 x 9.1 mm (6.43 x 3.03 x 0.36 in) 132.9 x 69.2 x 10.3 mm (5.23 x 2.72 x 0.41 in)
SIM Nano-SIM + Nano-SIM Single SIM (Micro-SIM) or Hybrid Dual SIM (Micro-SIM, dual stand-by)
Weight 198 g (6.98 oz) 143 g (5.04 oz)
Comms
Bluetooth 5.0, A2DP, LE 4.0, A2DP, LE
Infrared port Yes -
NFC Yes (market/region dependent) No
Positioning GPS, GLONASS, BDS GPS, GLONASS
Radio Wireless FM radio (no wired headphones required) FM radio
USB USB Type-C 2.0, OTG microUSB 2.0, OTG
WLAN Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct Wi-Fi 802.11 b/g/n, Wi-Fi Direct
Display
Protection Corning Gorilla Glass 3 -
Resolution 1080 x 2340 pixels, 19.5:9 ratio (~395 ppi density) 480 x 800 pixels, 5:3 ratio (~207 ppi density)
Size 6.53 inches, 104.7 cm2 (~83.2% screen-to-body ratio) 4.5 inches, 57.6 cm2 (~62.7% screen-to-body ratio)
Type IPS LCD, 400 nits (typ) IPS LCD
Features
Sensors Fingerprint (rear-mounted), accelerometer, proximity, compass Accelerometer, proximity
Launch
Announced 2020, June 10 2017, May. Released 2017, June
Status Available. Released 2020, June 10 Discontinued
Main Camera
Features LED flash, HDR, panorama Dual-LED flash, panorama, HDR
Quad 13 MP, f/2.2, 28mm (wide), 1/3.1", 1.12µm, PDAF 8 MP, f/2.2, 118˚ (ultrawide), 1/4.0", 1.12µm 5 MP, f/2.4, (macro) 2 MP, f/2.4, (depth) -
Single - 5 MP, f/2.2
Video 1080p@30fps 720p@30fps
Memory
Card slot microSDXC (dedicated slot) microSDXC (uses shared SIM slot)
Internal 32GB 3GB RAM, 64GB 4GB RAM, 128GB 4GB RAM, 128GB 6GB RAM 8GB 1GB RAM
  eMMC 5.1 -
Misc
Colors Carbon Gray, Sunset Purple, Ocean Green, Pink/Blue Black, Gold
Models M2004J19G, M2004J19C SM-Z400F, SM-Z400Y
SAR 0.91 W/kg (head)     1.00 W/kg (body)     -
SAR EU 0.71 W/kg (head)     1.06 W/kg (body)     -
Network
2G bands GSM 850 / 900 / 1800 / 1900 GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 (dual-SIM model only)
3G bands HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100 HSDPA 900 / 2100
4G bands 1, 2, 3, 4, 5, 7, 8, 20, 28, 38, 40, 41 LTE
Speed HSPA, LTE HSPA 42.2/5.76 Mbps, LTE Cat4 150/50 Mbps
Technology GSM / HSPA / LTE GSM / HSPA / LTE
Our Tests
Battery (old) Endurance rating 131h -
Camera Photo / Video -
Display 1624:1 contrast ratio, 328 nits max brightness (measured) -
Loudspeaker -26.9 LUFS (Good) -
Performance AnTuTu: 201829 (v8) GeekBench: 1325 (v5.1) -
Platform
Chipset Mediatek MT6769V/CU Helio G80 (12 nm) -
CPU Octa-core (2x2.0 GHz Cortex-A75 & 6x1.8 GHz Cortex-A55) Quad-core 1.5 GHz
GPU Mali-G52 MC2 -
OS Android 10, upgradable to Android 12, MIUI 13 Tizen 3.0
Selfie camera
Features HDR LED flash
Single 8 MP, f/2.0, 27mm (wide), 1/4.0", 1.12µm 5 MP, f/2.2
Video 1080p@30fps
Sound
3.5mm jack Yes Yes
Loudspeaker Yes Yes