Compare phones
| Global Score | |
| 98.1 | 85.5 |
| Basic Information | |
| Samsung | Samsung |
| Android 11 | Android 11, 10 |
| 2021-01-29 | 2019-12-27 |
| 6.50 x 2.98 x 0.35 inches | 6.24 x 2.90 x 0.31 inches |
| 8.04 ounces | 6.07 ounces |
| Phantom black and Silver | Prism Crush black, Prism Crush blue, Prism Crush pink and Prism Crush white |
| Aluminum and Glass (Corning Gorilla Glass Victus) | Plastic and Plastic |
| Scratch-Resistant Glass | Scratch-Resistant Glass |
| $ 966.00 | $ 282.00 |
| Display / Screen | |
| 6.8 inches | 6.5 inches |
| 3200 x 1440 pixels | 2400 x 1080 pixels |
| Dynamic AMOLED | Super AMOLED |
| 516 pixels per inch | 405 pixels per inch |
| 1500 cd/m2 brightness | -- |
| No touch screen | No touch screen |
| 9.8 | 8.1 |
| Performance | |
| Qualcomm Snapdragon 888 chipset | Samsung Exynos 9611 chipset |
| Kryo 680, 64-bit, 5 nm (Octa-Core 2840 MHz) processor | ARM Cortex-A73 and ARM Cortex-A53, 64-bit, 10 nm (Octa-Core 2300 MHz) processor |
| 12 GB RAM | 4 GB RAM |
| Adreno 660 GPU | Mali-G72 MP3 GPU |
| 9.72 | 9.27 |
| Storage | |
| 128 GB internal memory | 128 GB internal memory |
| No SD card slot | microSDXC (up to 512 GB) external memory slot |
| 10.1 | 14.14 |
| Camera | |
| 108.00 MP + 40.00 MP | 48.00 MP + 32.00 MP |
| f/1.80 aperture | f/2.00 aperture |
| 24.00mm focal length | 26.00mm focal length |
| 0.75 inches (1/1.33") sensor | 0.5 inches (1/2") sensor |
| 7680 x 4320 (24 fps) video resolution | 3840 x 2160 (30 fps) (4K) video resolution |
| 1280 x 720 (960 fps) (HD) slow motion video | 1280 x 720 (240 fps) (HD) slow motion video |
| 13.75 | 11.55 |
| Networks | |
| Wi-Fi | Wi-Fi |
| Mobile Hotspot | Mobile Hotspot |
| 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA | LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA |
| Nano SIM | Nano SIM, Dual SIM |
| 10.7 | 6.7 |
| Battery Life | |
| 5000mAh Li - Polymer Battery | 4000mAh Li - Polymer Battery |
| Non-Removable Battery | Non-Removable Battery |
| Wireless Charging | -- |
| 6.8 | 5.92 |
| Other Features | |
| Bluetooth 5.1 | Bluetooth 5.0 |
| GPS | GPS |
| NFC | NFC |
| Fingerprint ID Scanner | Fingerprint ID Scanner |
| Accelerometer, Barometer, Compass, Gyroscope, Light Sensor and Proximity Sensor | Accelerometer, Compass, Gyroscope, Light Sensor and Proximity Sensor |
| FM Radio | FM Radio |
Comparison review
Samsung Galaxy S21 Ultra has a global score of 98.1, which is much better than Samsung Galaxy A51's 85.5 global score. Samsung Galaxy S21 Ultra is a newer phone than the Samsung Galaxy A51, but it is heavier and somewhat thicker. Both of these devices come with the same Android 11 OS (Operating System), so both of them should give you identical OS features.
Galaxy S21 Ultra counts with a much better looking screen than Samsung Galaxy A51, because it has a better resolution of 1440 x 3200px, a bit bigger screen and a greater pixels density. Galaxy A51 features much more memory to install games and applications than Samsung Galaxy S21 Ultra, and although they both have exactly the same 128 GB internal memory, the Galaxy A51 also has a SD memory slot that allows a maximum of 512 GB.
Galaxy S21 Ultra features a bit better processor than Galaxy A51, and although they both have 8 cpu cores, the Galaxy S21 Ultra also has a greater amount of RAM. The Galaxy S21 Ultra takes better pictures and videos than Galaxy A51, because it has a much bigger back camera sensor taking way higher quality videos and pictures, a back camera with a much higher 108 MP resolution, a bigger camera aperture to capture better low light images and video and a way higher 7680x4320 video definition.
The Galaxy S21 Ultra features longer battery lifetime than Galaxy A51, because it has 5000mAh of battery capacity.
Although Samsung Galaxy S21 Ultra is a better device, it is way more expensive than Galaxy A51, and it doesn't have such a good quality/price relation as the Galaxy A51. So if you want that extra specs and features, you can buy Samsung Galaxy S21 Ultra, otherwise you can save some dollars and get the Galaxy A51, resigning some features and specifications.
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