Compare phones
| Global Score | |
| 82.6 | 98.1 |
| Basic Information | |
| Samsung | Samsung |
| Android 14 | Android 11 |
| -- | 2021-01-29 |
| -- | 6.50 x 2.98 x 0.35 inches |
| -- | 8.04 ounces |
| -- | Phantom black and Silver |
| Aluminum and Glass (Corning Gorilla Glass Victus 2) | Aluminum and Glass (Corning Gorilla Glass Victus) |
| Scratch-Resistant Glass | Scratch-Resistant Glass |
| $ 800.00 | $ 966.00 |
| Display / Screen | |
| 6.2 inches | 6.8 inches |
| 2340 x 1080 pixels | 3200 x 1440 pixels |
| Dynamic AMOLED | Dynamic AMOLED |
| 416 pixels per inch | 516 pixels per inch |
| 2600 cd/m2 brightness | 1500 cd/m2 brightness |
| No touch screen | No touch screen |
| 9.7 | 9.8 |
| Performance | |
| Qualcomm Snapdragon 8 Gen 4 chipset | Qualcomm Snapdragon 888 chipset |
| processor | Kryo 680, 64-bit, 5 nm (Octa-Core 2840 MHz) processor |
| 8 GB RAM | 12 GB RAM |
| Yes GPU | Adreno 660 GPU |
| 6.21 | 9.72 |
| Storage | |
| 128 GB internal memory | 128 GB internal memory |
| No SD card slot | No SD card slot |
| 10.1 | 10.1 |
| Camera | |
| 50.00 MP + 12.00 MP | 108.00 MP + 40.00 MP |
| f/1.80 aperture | f/1.80 aperture |
| 24.00mm focal length | 24.00mm focal length |
| 0.64 inches (1/1.56") sensor | 0.75 inches (1/1.33") sensor |
| 7680 x 4320 (30 fps) video resolution | 7680 x 4320 (24 fps) video resolution |
| 1920 x 1080 (240 fps) (Full HD) slow motion video | 1280 x 720 (960 fps) (HD) slow motion video |
| 12.54 | 13.75 |
| Networks | |
| Wi-Fi | Wi-Fi |
| Mobile Hotspot | Mobile Hotspot |
| 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G) and HSDPA | 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA |
| Nano SIM | Nano SIM |
| 10.6 | 10.7 |
| Battery Life | |
| 4000mAh Li - Ion Battery | 5000mAh Li - Polymer Battery |
| Non-Removable Battery | Non-Removable Battery |
| Wireless Charging | Wireless Charging |
| 5.92 | 6.8 |
| Other Features | |
| Bluetooth 5.3 | Bluetooth 5.1 |
| GPS | GPS |
| NFC | NFC |
| Fingerprint ID Scanner | Fingerprint ID Scanner |
| Accelerometer, Barometer, Compass, Gyroscope, Light Sensor and Proximity Sensor | Accelerometer, Barometer, Compass, Gyroscope, Light Sensor and Proximity Sensor |
| -- | FM Radio |
Comparison review
The Samsung Galaxy S21 Ultra has an overall score of 98.1, which is much better than the Galaxy S25's global score of 82.6. Both devices in our current comparison come with Android OS (operating system), but Samsung Galaxy S21 Ultra has older 11 version and Galaxy S25 has Android 14. The Galaxy S21 Ultra features a really superior processing power than Samsung Galaxy S25, and although they both have a Octa-Core processor, the Galaxy S21 Ultra also has a higher amount of RAM memory.
The Galaxy S21 Ultra has a bit better screen than Galaxy S25, because although it has a lot more opaque screen, it also counts with a better 1440 x 3200 resolution, a little bit bigger display and a just a bit more pixels per screen inch. The Galaxy S21 Ultra takes clearer photographs and videos than Samsung Galaxy S25, because although it has lower 24 fps video frame rate, and they both have the same video quality and a same size diafragm aperture, the Galaxy S21 Ultra also counts with a larger back-facing camera sensor capturing higher quality photographs and videos and a much more mega pixels camera in the back.
The Galaxy S25 and the Galaxy S21 Ultra feature extremely similar memory capacity for apps and games, both have exactly the same internal storage. The Galaxy S21 Ultra has superior battery performance than Galaxy S25, because it has a 5000mAh battery size.
Galaxy S21 Ultra costs more money than the Samsung Galaxy S25, but it's still a great deal, as you can get a better phone for that extra money.
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