Compare phones
| Global Score | |
| 72.6 | 98.1 |
| Basic Information | |
| Samsung | Samsung |
| Android 15 | 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) |
| -- | Scratch-Resistant Glass |
| -- | $ 966.00 |
| Display / Screen | |
| 6.8 inches | 6.8 inches |
| -- | 3200 x 1440 pixels |
| AMOLED | Dynamic AMOLED |
| -- | 516 pixels per inch |
| -- | 1500 cd/m2 brightness |
| No touch screen | No touch screen |
| 2.7 | 9.8 |
| Performance | |
| Qualcomm Snapdragon 8 Elite SM8650 (4 nm) chipset | Qualcomm Snapdragon 888 chipset |
| processor | Kryo 680, 64-bit, 5 nm (Octa-Core 2840 MHz) processor |
| 12 GB RAM | 12 GB RAM |
| Adreno 830 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 | |
| 200.00 MP + 10.00 MP | 108.00 MP + 40.00 MP |
| -- | f/1.80 aperture |
| -- | 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 |
| 13.42 | 13.75 |
| Networks | |
| -- | Wi-Fi |
| -- | 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 |
| 7.6 | 10.7 |
| Battery Life | |
| 3050mAh Dual Nano SIM + eSIM Battery | 5000mAh Li - Polymer Battery |
| Non-Removable Battery | Non-Removable Battery |
| Wireless Charging | Wireless Charging |
| 5.04 | 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
Galaxy S21 Ultra has an overall score of 98.1, which is way better than Samsung Galaxy S25 Slim (Rumored)'s 72.6 score. Both phones we compare here work with Android operating system, but Galaxy S21 Ultra has the older 11 version while Samsung Galaxy S25 Slim (Rumored) has Android 15 version. Samsung Galaxy S21 Ultra counts with a way better looking screen than Galaxy S25 Slim (Rumored). Both of them have a screen with the same size.
Samsung Galaxy S21 Ultra's memory capacity for applications, games, photos and videos is just as good as the Galaxy S25 Slim (Rumored) one, they have the same internal storage. Galaxy S21 Ultra has a very superior processing power than Galaxy S25 Slim (Rumored), and although they both have a 12 GB RAM memory, the Galaxy S21 Ultra also has a greater number of cores (and they are faster).
Samsung Galaxy S21 Ultra counts with a superior battery duration than Samsung Galaxy S25 Slim (Rumored), because it has a 64% greater battery size. Samsung Galaxy S21 Ultra has a slightly better camera than Galaxy S25 Slim (Rumored), because although it has a back facing camera with a lot worse 108 MP resolution and a lower 7680x4320 video definition, it also counts with a larger sensor capturing more light and vivid colors.
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