Compare phones
| Global Score | |
| 98.1 | 82.6 |
| Basic Information | |
| Samsung | Samsung |
| Android 11 | Android 14 |
| 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) | Aluminum and Glass (Corning Gorilla Glass Victus 2) |
| Scratch-Resistant Glass | Scratch-Resistant Glass |
| $ 966.00 | $ 800.00 |
| Display / Screen | |
| 6.8 inches | 6.2 inches |
| 3200 x 1440 pixels | 2340 x 1080 pixels |
| Dynamic AMOLED | Dynamic AMOLED |
| 516 pixels per inch | 416 pixels per inch |
| 1500 cd/m2 brightness | 2600 cd/m2 brightness |
| No touch screen | No touch screen |
| 9.8 | 9.7 |
| Performance | |
| Qualcomm Snapdragon 888 chipset | Qualcomm Snapdragon 8 Gen 4 chipset |
| Kryo 680, 64-bit, 5 nm (Octa-Core 2840 MHz) processor | processor |
| 12 GB RAM | 8 GB RAM |
| Adreno 660 GPU | Yes GPU |
| 9.72 | 6.21 |
| Storage | |
| 128 GB internal memory | 128 GB internal memory |
| No SD card slot | No SD card slot |
| 10.1 | 10.1 |
| Camera | |
| 108.00 MP + 40.00 MP | 50.00 MP + 12.00 MP |
| f/1.80 aperture | f/1.80 aperture |
| 24.00mm focal length | 24.00mm focal length |
| 0.75 inches (1/1.33") sensor | 0.64 inches (1/1.56") sensor |
| 7680 x 4320 (24 fps) video resolution | 7680 x 4320 (30 fps) video resolution |
| 1280 x 720 (960 fps) (HD) slow motion video | 1920 x 1080 (240 fps) (Full HD) slow motion video |
| 13.75 | 12.54 |
| Networks | |
| Wi-Fi | Wi-Fi |
| Mobile Hotspot | Mobile Hotspot |
| 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA | 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G) and HSDPA |
| Nano SIM | Nano SIM |
| 10.7 | 10.6 |
| Battery Life | |
| 5000mAh Li - Polymer Battery | 4000mAh Li - Ion Battery |
| Non-Removable Battery | Non-Removable Battery |
| Wireless Charging | Wireless Charging |
| 6.8 | 5.92 |
| Other Features | |
| Bluetooth 5.1 | Bluetooth 5.3 |
| 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
Samsung Galaxy S21 Ultra has a general score of 98.1, which is better than Galaxy S25's general score of 82.6. Both phones in our current comparison work with Android operating system, but the Samsung Galaxy S21 Ultra has the older 11 version and Galaxy S25 has Android 14. The Samsung Galaxy S21 Ultra has an extremely better processing unit than Samsung Galaxy S25, and although they both have 8 processing cores, the Samsung Galaxy S21 Ultra also has more RAM memory.
The Samsung Galaxy S21 Ultra counts with a little bit better screen than Samsung Galaxy S25, because although it has a lot darker screen, it also counts with a little bit better display pixel density, a higher 1440 x 3200 resolution and a quite bigger display. The Samsung Galaxy S21 Ultra features just a bit better camera than Galaxy S25, because although it has slower video frame rate, and they both have the same aperture and the same 7680x4320 video resolution, the Samsung Galaxy S21 Ultra also counts with a bigger sensor and a way higher 108 megapixels resolution camera.
Samsung Galaxy S25 has as much memory capacity to install games and applications as the Samsung Galaxy S21 Ultra, both have equal internal storage. The Galaxy S21 Ultra features better battery lifetime than Galaxy S25, because it has a 5000mAh battery size instead of 4000mAh.
The Samsung Galaxy S21 Ultra is more expensive than Galaxy S25, but you can get a better phone for that extra money.
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