Samsung Galaxy S24 Ultra (SM-S928U 256GB) vs Samsung Galaxy S21
Side by side comparison between Samsung Galaxy S24 Ultra vs Samsung Galaxy S21 phones, differences, pros, cons and full specifications. What's the better?
,
6.8"
AMOLED
AMOLED
1440x3120
200
MP
MP
12mp
12GB
RAM
RAM
Octa-core
5000
mAh
mAh
(Non removable)
vs
6.2"
AMOLED
AMOLED
1080x2400
12.2
MP
MP
10mp
8GB
RAM
RAM
Octa-core
4000
mAh
mAh
(Non removable)
What's the better phone? Samsung Galaxy S24 Ultra (SM-S928U 256GB)
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!
17 Advantages 
3 Advantages | 36 Common items in both devices |
| Dynamic AMOLED |
| HDR10+ |
| 120Hz |
| 16 million |
| LED flash |
| Digital and optical zoom |
| PDAF: phase detection autofocus / PDAF: phase detection autofocus on both cameras |
| +29 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 | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Model | Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 |
| Other model names | Galaxy S24 Ultra SM-S928U1 | Galaxy S21 5G SM-G991B/DS |
| Country or region available |  USA |  (Global, International) |
| Brand | Samsung | Samsung |
| Release date | 1/24/2024, Announced: 1/17/2024 | 1/29/2021, Announced: 1/14/2021 |
| Depth | 8.6 millimeters (0.34 inches) | 7.9 millimeters (0.31 inches) |
| Size (width x height) | 79 x 162.3 millimeters (3.11 x 6.39 in) | 71.2 x 151.7 millimeters (2.8 x 5.97 in) |
| Weight | 232 grams (8.12 ounces) | 169 grams (5.92 ounces) |
| Build, materials | Titanium frame, glass front and back Back: Gorilla Armor | Aluminum body, glass front, plastic back |
| Protection against water and others | IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant | IP68 certified: water-resistant up to 1.5 meters for 30min and dust-resistant |
📲 Display | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Display type | Dynamic AMOLED | Dynamic AMOLED |
| Screen size | 6.8" inches | 6.2" inches |
| Screen-to-body ratio | ~88.5% (screen-to-body ratio) | ~85.9% (screen-to-body ratio) |
| Display resolution | 1440x3120 pixels (19.5:9) | 1080x2400 pixels (20:9) |
| Touchscreen | Capacitive Multitouch 10-points | Capacitive Multitouch 10-points |
| Pixel density (dot pitch) | 505 PPI | 424 PPI |
| Colors | 16 million | 16 million |
| Scratch-resistant glass | Gorilla Armor | Gorilla Glass Victus |
| Refresh rate | 120Hz | 120Hz |
| Display features | 2600nits[peak] HDR10+ Always-On Display | 1300nits[peak] HDR10+ Always-On Display |
🤖 Operating System | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| System version | Android 14 | Android 11 |
| Firmware update | feature not registered | Android 14 |
| User Interface | One UI 6.1 | One UI 3.1 / 4.1 / 5.1 / 6.0 |
⚙️ Processor | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Chipset | 64bit: Qualcomm Snapdragon 8 Gen 3 (SM8650-AC) (4nm) | 64bit: Samsung Exynos 2100 (5nm) |
| CPU | Octa-core, 4 processors: 1x 3.4GHz ARM Cortex-X4 (Single-core) 3x 3.15GHz ARM Cortex-A720 (Triple-core) 2x 2.96GHz ARM Cortex-A720 (Dual-core) 2x 2.27GHz ARM Cortex-A520 (Dual-core) | 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) |
| GPU graphical controller | Qualcomm Adreno 750 (1GHz) | ARM Mali-G78 MP14 (854MHz) |
| Performance (benchmark) | AnTuTu: 1452915 (v9), 1822988 (v10) Geekbench: 7076 (v6) | feature not registered |
💽 Memory and storage | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| RAM memory | 12GB LPDDR5X | 8GB LPDDR5 |
| Internal storage | 256GB (226GB available) UFS 4.0 | 128GB (104GB available) UFS 3.1 |
| External storage | Not supported | Not supported |
📶 Mobile networks | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Dual-SIM | Dual-SIM Standby - Call active on one sim card | Dual-SIM Standby - Call active on one sim card |
| SIM card | 1 slot (Single-SIM) nano-SIM (4FF) + e-SIM | 2 slots (Dual-SIM) nano-SIM (4FF) + e-SIM |
| Maximum Download / Upload | 5000/1024 Mbps | 5000/1920 Mbps |
| Network technology | 2G, 3G, 4G, 5G | 2G, 3G, 4G, 5G |
| 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 | CDMA 800/1900, GSM 850/900/1800/1900 | CDMA 800/1900, GSM 850/900/1800/1900 |
| Primary 3G network | CDMA2000 1xEV-DO UMTS 850/900/1700/1900/2100 | CDMA2000 1xEV-DO TD-SCDMA 1900/2000 UMTS 850/900/1700/1900/2100 |
| Primary 4G network | LTE Cat20 (1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 29, 30, 66, 71) TD-LTE (38, 39, 40, 41, 46, 48) VoLTE | LTE Cat24 () TD-LTE () VoLTE |
| Primary 5G network | SA/NSA/Sub6 (1, 2, 3, 5, 7, 8, 20, 25, 38, 41, 66, 71, 77, 78) mmWave (260, 261) | SA/NSA/Sub6 () |
| Primary data network | GPRS, EDGE, CDMA2000 EV-DO Rev 0, CDMA2000 EV-DO Rev A, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA, Sub6, mmWave | GPRS, EDGE, CDMA2000 EV-DO Rev 0, CDMA2000 EV-DO Rev A, TD-SCDMA, UMTS, TD-HSDPA, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA, Sub6 |
| Secondary 2G network | CDMA 800/1900, GSM 850/900/1800/1900 | GSM 850/900/1800/1900 |
| Secondary 3G network | CDMA2000 1xEV-DO 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, 14, 18, 19, 20, 25, 26, 28, 29, 30, 66, 71) TD-LTE (38, 39, 40, 41, 46, 48) VoLTE | LTE Cat24 () TD-LTE () VoLTE |
| Secondary data network | GPRS, EDGE, CDMA2000 EV-DO Rev 0, CDMA2000 EV-DO Rev A, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A, SA/NSA, Sub6, mmWave | GPRS, EDGE, UMTS, HSDPA, HSUPA, HSPA+, TD-LTE, LTE, LTE-A |
📷 Camera | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Back camera (main camera) | (quad camera) 200 megapixels 50MP periscope telephoto f/3.4111mmPDAFOIS5x-optical-zoom 12MP ultrawide f/2.213mm120°1/2.55"1.4µmPDAFSuper-Steady 10MP telephoto f/2.467mm1/3.52"1.12µmPDAFOIS3x-optical-zoom | (triple camera) 12.2 megapixels 64MP telephoto f/2.029mm1/1.72"0.8µmPDAFOIS1.1x-optical-zoom3x-hybrid-zoom 12MP ultrawide f/2.213mm120°1/2.55"1.4µmSuper-Steady-video |
| Main camera resolution | 20000x10000 pixels | 4032x3024 pixels |
| Video recording (primary) | 8K UHD (7680x4320) 30 fps | 8K UHD (7680x4320) 24 fps |
| Flash | LED flash | LED flash |
| Focal aperture | f/1.8 (aperture) | f/1.8 (aperture) |
| Focal length | 24mm lens | 26mm lens |
| Sensor size | 1/1.56" inches | 1/1.76" inches |
| Pixel size | 1µm pixel | 1.8µm pixel |
| Autofocus | PDAF: phase detection autofocus | PDAF: phase detection autofocus on both cameras |
| Touch focus | Supported | Supported |
| Image stabilization | OIS: Optical stabilization | OIS: Optical stabilization |
| Zoom | Digital and optical zoom | Digital and optical 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/video on both cameras |
| Camera extras | 8K@24/30fps 4K@30/60/120fps 1080p@30/60/240fps HDR10+ | 4K@60fps 1080p@240fps 720p@960fps |
📸 Front camera | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Front camera (secondary) | 12 megapixels | 10 megapixels |
| Front camera resolution | 4000x3000 pixels | 3872x2592 pixels |
| Video recording (secondary) | 4K UHD (3840x2160) | 4K UHD (3840x2160) |
| Front flash | Not supported | Not supported |
| Focal aperture | f/2.2 (aperture) | f/2.2 (aperture) |
| Focal length | 26mm lens | 26mm lens |
| Sensor size | feature not registered | 1/3.24" inches |
| Pixel size | feature not registered | 1.22µm pixel |
🔉 Sound and multimedia | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Loudspeaker | Stereo sound 32-bit/384kHz Tuned by AKG | Stereo sound 32-bit/384kHz Dolby Atmos Tuned by AKG |
| Active noise cancellation | 2 microphones or more | 2 microphones or more |
| Radio | Not supported | 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 S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| USB | USB 3.2 Type-C, USB OTG On-The-Go | USB 3.2 Type-C, USB OTG On-The-Go |
| Audio output | Type-C reversible connector | Type-C reversible connector |
| TV output | USB Type-C (reversible) | USB Type-C (reversible) |
| Bluetooth | 5.3 + A2DP/LE | 5.0 + A2DP/LE |
| WiFi | 802.11 a/b/g/n/ac/ax/be [wifi7/6E/6] (2.4GHz, 5GHz, 6GHz) + MIMO WiFi Direct, hotspot | 802.11 a/b/g/n/ac/ax [wifi6] (2.4GHz, 5GHz) + MIMO WiFi Direct, hotspot |
| DLNA | Supported | Supported |
| GPS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou, QZSS | A-GPS, GeoTagging, GLONASS, GALILEO, BeiDou |
| NFC | Supported | Supported |
| Infrared port | Not supported | Not supported |
🧭 Sensors | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Sensors | Accelerometer Ambient light sensor Barometer Compass Face unlock Fingerprint sensor (under display) Gyroscope Hall effect Proximity sensor UWB (Ultra Wideband) | Accelerometer Ambient light sensor Barometer Compass Face unlock Fingerprint sensor (under display) Gesture Gyroscope Hall effect Proximity sensor |
| Vibrating alert | Supported | Supported |
🔋 Battery | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| Battery type | Li-Ion: lithium-ion (Non removable) | LiPo: li-ion polymer (Non removable) |
| Battery capacity | 5000 mAh | 4000 mAh |
| Charger, watts | 45W Wired fast charging Reverse charging by cable | 25W Wired fast charging USB Power Delivery 3.0 |
| Inductive / wireless charging | 15W Qi wireless charging (Qi/PMA) 4.5W Reverse wireless charging | 15W Qi wireless charging (Qi/PMA) 4.5W Reverse wireless charging |
| Talk time autonomy | feature not registered | feature not registered |
| Standby | feature not registered | feature not registered |
➕ Other features | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| 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: Titanium Black, Gray, Violet, Yellow, Blue, Green, Orange • Samsung DeX • Stylus pen (Bluetooth) | • Colors: Phantom Gray, White, Violet, Pink • Samsung Pay (Visa, MasterCard) • Samsung DeX |
☢️ Radiation rate | ||
| Galaxy S24 Ultra (SM-S928U 256GB) | Galaxy S21 | |
| SAR 1.6W/kg (USA, Mexico, etc.) | 1.26W/kg (head), 0.62W/kg (body) | feature not registered |
| SAR 2W/kg (Europe, UK, etc.) | feature not registered | 0.456W/kg (head), 1.509W/kg (body) |