Samsung Galaxy S21 Ultra (SM-G998B/DS 128GB) vs Xiaomi Redmi Note 9 (128GB/4GB)

Share page: Facebook Twitter WhatsApp Share page:

Side by side comparison between Samsung Galaxy S21 Ultra vs Xiaomi Redmi Note 9 phones, differences, pros, cons and full specifications. What's the better?

1/16/2021 4:45 PM, updated: 9/27/2024 2:43 AM

Compare Xiaomi Redmi Note 9 X Samsung Galaxy S21 Ultra (SM-G998B/DS 128GB) 32Points

Specifications Compare Models Pictures

6.8"
AMOLED

1440x3200

108
MP

40mp

12GB
RAM

Octa-core

5000
mAh

(Non removable)

04Points Xiaomi Redmi Note 9 (128GB/4GB) Compare Samsung Galaxy S21 Ultra X

Specifications Compare Models Pictures

6.53"
IPS

1080x2340

48
MP

13mp

4GB
RAM

Octa-core

5020
mAh

(Non removable)

What's the better phone? Samsung Galaxy S21 Ultra (SM-G998B/DS 128GB)

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!

32 Advantages Samsung Galaxy S21 Ultra (SM-G998B/DS 128GB)	vs	4 Advantages Xiaomi Redmi Note 9 (128GB/4GB)
+2.9GHz 64bit Octa-core (5nm)34% More powerful processor, you can open your applications faster	vs	2GHz 64bit Octa-core (12nm)
+12GB LPDDR52 times More RAM memory. Typically more responsive and better for multitasking.	vs	4GB LPDDR4X
+UFS 3.1Advantage Fastest write and read storage.	vs	eMMC 5.1
+Aluminum frame, glass front/backAdvantage More resistant material	vs	Plastic body, glass front
+Dynamic AMOLEDAdvantage Dynamic AMOLED display is brighter and more vivid	vs	TFT IPS LCD
+HDR10+Advantage The HDR10+ display provides vibrant colors and more details	vs	Not supported
+120Hz100% The display reproduces more frames per second because the frequency (Hertz) is higher, improves fluidity and tires your eyes less.	vs	60Hz
+1440x3200 pixels82% Higher resolution screen	vs	1080x2340 pixels
+516 PPI31% Crisper display of text, images and videos because it has more pixels per inch (ppi)	vs	395 PPI
+6.8"4% Larger screen	vs	6.53"
+(quad camera) 108MP + 10MP + 10MP + 12MP133% Higher resolution main camera	vs	(quad camera) 48MP + 8MP + 2MP + 2MP
+Digital and optical zoomAdvantage The zoom allows for better focus and approach to take pictures	vs	Only digital zoom
+OIS: Optical stabilizationAdvantage Image stabilization prevents blurry photos and helps in recording motion video	vs	EIS: Digital stabilization
+1/1.33" inches50% The larger sensor camera lets you take photos with better depth.	vs	1/2" inches
+(front) 40MP2 times Higher resolution secondary camera to take pictures and selfies	vs	(front) 13MP
+8K UHD (7680x4320)15 times More image quality for recording videos with the primary camera	vs	Full HD (1920x1080)
+(front) 4K UHD (3840x2160)3 times More image quality for recording videos with the secondary camera	vs	(front) Full HD (1920x1080)
+Android 14Advantage Android 14 is newer and safer	vs	Android 11
+5G SA/NSAAdvantage The 5G SA/NSA network is newer and faster	vs	4G LTE-A
+(5G SA/NSA) 5000 Mbps16 times Faster for surfing the internet and download files	vs	(4G LTE-A) 300 Mbps
+BarometerAdvantage Sensors help you use the device	vs	Not supported
+UWB (Ultra Wideband)Advantage Sensors help you use the device	vs	Not supported
+25W39% More power (watts) to charge the battery faster. Sometimes, the charger that comes with the device doesn't have the same power supported by the device. Check before you buy it.	vs	18W
+Qi wireless charging (Qi/PMA)Advantage Wireless charging is another way to charge the battery.	vs	Not supported
+2 slots (Dual-SIM) + e-SIM (Eletronic)Advantage You can have more mobile carriers/operators on the same device.	vs	2 slots (Dual-SIM) (dedicated slot)
+Stereo soundAdvantage Better sound quality for listening to music or clearer hands-free calls	vs	Mono sound (not stereo)
+802.11 a/b/g/n/ac/ax [wifi6]Advantage WiFi 802.11 a/b/g/n/ac/ax [wifi6] is newer and faster	vs	802.11 a/b/g/n/ac [wifi5]
+DLNAAdvantage With DLNA technology you can access and play media files on TV, tablet or DLNA compatible device.	vs	Not supported
+5.2 + A2DP/LEAdvantage Bluetooth 5.2 + A2DP/LE is newer and faster	vs	5.0 + A2DP/LE
+NFCAdvantage NFC allows you to make payments by approach quickly and securely	vs	Not supported
+USB 3.2 Type-C, USB OTG On-The-GoAdvantage Newer and faster USB version for transferring photos, mp3 or data.	vs	USB 2.0 Type-C, USB OTG On-The-Go
+IP68 certifiedAdvantage Protection against water allows you talk to your friends in the rain, for example	vs	Water repellent nano-coating (don't immerse)
Not supported	vs	+Until 512GB microSD, microSDXCAdvantage More external storage for files using memory cards
227 grams (7.95 ounces)	vs	+199 grams (6.97 ounces)14% Lighter
5000 mAh	vs	+5020 mAh1% Battery - higher amperage (mAh) allows more device usage time, but it also depends on the hardware and use
Type-C reversible connector	vs	+3.5mm jackAdvantage Headsets with 3.5mm Jack size are more common and easy to find in stores

26 Common items in both devices

128GB (101GB available) / 128GB (106GB available)

8.9 millimeters (0.35 inches)

16 million

LED flash

PDAF: phase detection autofocus on both cameras / PDAF: phase detection autofocus

BSI sensor

HDR photo/video on both cameras / HDR photo on both cameras

+19 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

📱 Model features
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Change model		Choose the model
Model	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Other model names	Galaxy S21 Ultra 5G (SM-G998B/Dual-SIM)	Mi Redmi Note 9 CX296VRD, CX296CIN, M2003J15SS/2003J15SC
Country or region available	(Global, International)	Brazil, China, India
Brand	Samsung	Xiaomi
Release date	1/29/2021, Announced: 1/14/2021	5/12/2020, Announced: 4/30/2020
Depth	8.9 millimeters (0.35 inches)	8.9 millimeters (0.35 inches)
Size (width x height)	75.6 x 165.1 millimeters (2.98 x 6.5 in)	77.2 x 162.3 millimeters (3.04 x 6.39 in)
Weight	227 grams (7.95 ounces)	199 grams (6.97 ounces)
Build, materials	Aluminum frame, glass front/back	Plastic body, glass front
Protection against water and others	IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant	Water repellent nano-coating (don't immerse)
📲 Display
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Display type	Dynamic AMOLED	TFT IPS LCD
Screen size	6.8" inches	6.53" inches
Screen-to-body ratio	~89.4% (screen-to-body ratio)	~83.5% (screen-to-body ratio)
Display resolution	1440x3200 pixels (20:9)	1080x2340 pixels (19.5:9)
Touchscreen	Capacitive Multitouch 10-points	Capacitive Multitouch
Pixel density (dot pitch)	516 PPI	395 PPI
Colors	16 million	16 million
Scratch-resistant glass	Gorilla Glass Victus	Gorilla Glass 5
Refresh rate	120Hz	60Hz
Display features	1500nits[peak] HDR10+ Always-On Display	450nits[typ]
🤖 Operating System
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
System version	Android 11	Android 10
Firmware update	Android 14	Android 11
User Interface	One UI 3.1 / 4.1 / 5.1 / 6.0	MIUI 11 / 12
⚙️ Processor
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Chipset	64bit: Samsung Exynos 2100 (5nm)	64bit: MediaTek Helio G85 (12nm)
CPU	Octa-core, 3 processors: 1x 2.9GHz ARM Cortex-X1 (Single-core) 3x 2.8GHz ARM Cortex-A78 (Triple-core) 4x 2.2GHz ARM Cortex-A55 (Quad-core)	Octa-core, 2 processors: 2x 2GHz ARM-Cortex-A75 (Dual-core) 6x 1.8GHz ARM-Cortex-A55 (Hexa-core)
GPU graphical controller	ARM Mali-G78 MP14 (854MHz)	ARM Mali-G52 MC2 (1GHz)
Performance (benchmark)	AnTuTu: 657150 (v8), 727634 (v9) Geekbench: 3457 (v5.2) GFXBench: 51fps (ES 3.1 onscreen)	AnTuTu: 200451 (v8) Geekbench: 1292 (v5.1)
💽 Memory and storage
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
RAM memory	12GB LPDDR5	4GB LPDDR4X
Internal storage	128GB (101GB available) UFS 3.1	128GB (106GB available) eMMC 5.1
External storage	Not supported	Until 512GB microSD, microSDXC (dedicated slot)
📶 Mobile networks
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Dual-SIM	Dual-SIM Standby - Call active on one sim card	Dual-SIM Standby - Call active on one sim card (dedicated slot)
SIM card	2 slots (Dual-SIM) nano-SIM (4FF) + e-SIM	2 slots (Dual-SIM) nano-SIM (4FF)
Maximum Download / Upload	5000/1920 Mbps	300/150 Mbps
Network technology	2G, 3G, 4G, 5G	2G, 3G, 4G
Frequency, bands	Expand band details Collapse details
GSM MHz band	Quad-Band 850/900/1800/1900	Quad-Band 850/900/1800/1900
Primary 2G network	GSM 850/900/1800/1900	GSM 850/900/1800/1900
Primary 3G network	UMTS 850/900/1700/1900/2100	UMTS 850/900/1700/1900/2100
Primary 4G network	LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 32, 66) TD-LTE (38, 39, 40, 41) VoLTE	LTE Cat7 (1, 2, 3, 4, 5, 7, 8, 20, 28) TD-LTE (38, 40, 41) VoLTE
Primary 5G network	SA/NSA/Sub6 (1, 3, 5, 7, 8, 20, 28, 38, 40, 41, 66, 77, 78)	Not supported
Primary data network	GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA	GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A
Secondary 2G network	GSM 850/900/1800/1900	GSM 850/900/1800/1900
Secondary 3G network	UMTS 850/900/1700/1900/2100	UMTS 850/900/1700/1900/2100
Secondary 4G network	LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 32, 66) TD-LTE (38, 39, 40, 41) VoLTE	LTE Cat7 (1, 2, 3, 4, 5, 7, 8, 20, 28) TD-LTE (38, 40, 41) VoLTE
Secondary data network	GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA	GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A
📷 Camera
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Back camera (main camera)	(quad camera) 108 megapixels 10MP periscope telephoto f/4.9240mm1/3.24"1.22µmPDAFOIS10x-optical-zoom 10MP telephoto f/2.470mm1/3.24"1.22µmPDAFOIS3x-optical-zoom 12MP ultrawide f/2.213mm1/2.55"1.4µmPDAFSuper-Steady-video	(quad camera) 48 megapixels 8MP ultrawide f/2.213mm1/4"1.12µm118° 2MP macro f/2.41.75µmAF 2MP depth f/2.41/5"1.7µm
Main camera resolution	12000x9000 pixels	8000x6000 pixels
Video recording (primary)	8K UHD (7680x4320) 24 fps	Full HD (1920x1080) 30 fps
Flash	LED flash	LED flash
Focal aperture	f/1.8 (aperture)	f/1.8 (aperture)
Focal length	26mm (lens)	26mm (lens)
Sensor size	1/1.33" inches	1/2" inches
Pixel size	1.8µm pixel	0.8µm pixel
Autofocus	PDAF: phase detection autofocus on both cameras	PDAF: phase detection autofocus
Touch focus	Supported	Supported
Image stabilization	OIS: Optical stabilization	EIS: Digital stabilization
Zoom	Digital and optical zoom	Only digital zoom
Face/smile detection	Face detection, Smile detection	Face detection, Smile detection
BSI sensor	Supported	Supported
HDR	HDR photo/video on both cameras	HDR photo on both cameras
Camera extras	4K@60fps 1080p@240fps 720p@960fps	feature not registered
📸 Front camera
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Front camera (secondary)	40 megapixels	13 megapixels
Front camera resolution	7296x5472 pixels	4128x3096 pixels
Video recording (secondary)	4K UHD (3840x2160)	Full HD (1920x1080)
Front flash	Not supported	Not supported
Focal aperture	f/2.2 (aperture)	f/2.3 (aperture)
Focal length	26mm (lens)	29mm (lens)
Sensor size	1/2.8" inches	1/3.06" inches
Pixel size	0.7µm pixel	1.12µm pixel
🔉 Sound and multimedia
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Loudspeaker	Stereo sound 32-bit/384kHz Dolby Atmos Tuned by AKG	Mono sound (not stereo)
Active noise cancellation	3 microphones	2 microphones or more
Radio	FM	FM
TV	Not supported	Not supported
Video formats	MP4, H.265, 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
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
USB	USB 3.2 Type-C, USB OTG On-The-Go	USB 2.0 Type-C, USB OTG On-The-Go
Audio output	Type-C reversible connector	3.5mm jack
TV output	USB Type-C (reversible)	USB Type-C (reversible)
Bluetooth	5.2 + A2DP/LE	5.0 + A2DP/LE
WiFi	802.11 a/b/g/n/ac/ax [wifi6] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot	802.11 a/b/g/n/ac [wifi5] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot
DLNA	Supported	Not supported
GPS	A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou	A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou
NFC	Supported	Not supported
Infrared port	Not supported	Supported
🧭 Sensors
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Sensors	Accelerometer Ambient light sensor Barometer Compass Face unlock Fingerprint sensor (under display) Gesture Gyroscope Hall effect Proximity sensor UWB (Ultra Wideband)	Accelerometer Ambient light sensor Compass Face unlock Fingerprint sensor (rear-mounted) Gyroscope Proximity sensor
Vibrating alert	Supported	Supported
🔋 Battery
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Battery type	LiPo: li-ion polymer (Non removable)	LiPo: li-ion polymer (Non removable)
Battery capacity	5000 mAh	5020 mAh
Charger, watts	25W Wired fast charging USB Power Delivery 3.0	18W Wired fast charging 9W Reverse charging by cable
Inductive / wireless charging	15W Qi wireless charging (Qi/PMA) 4.5W Reverse wireless charging	Not supported
Talk time autonomy	feature not registered	33 hours (1.4 days)
Standby	feature not registered	feature not registered
➕ Other features
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
Call control	Voice dialing, Voice recorder, Voice commands	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: Phantom Black, Silver, Titanium, Navy, Brown • Samsung Pay (Visa, MasterCard) • Samsung DeX • Stylus pen support	• Colors: Forest Green, Midnight Grey, Polar White • 22.5W charger (18W phone support)
☢️ Radiation rate
	Galaxy S21 Ultra (SM-G998B/DS 128GB)	Redmi Note 9 (128GB/4GB)
SAR 1.6W/kg (USA, Mexico, etc.)	0.24W/kg (head), 0.72W/kg (body)	0.84W/kg (head), 0.9W/kg (body)
SAR 2W/kg (Europe, UK, etc.)	0.714W/kg (head), 1.58W/kg (body)	0.8W/kg (head), 1.14W/kg (body)