Samsung Galaxy A51 vs Samsung Galaxy S25 Ultra

Our verdict: The Samsung Galaxy S25 Ultra wins on both fronts with a 6.8" screen and 505 PPI. Camera resolution goes to the Samsung Galaxy S25 Ultra with its 200MP rear shooter. Selfie fans take note: the Samsung Galaxy A51 has a 32MP front camera. You'll barely notice the Samsung Galaxy A51 in your pocket at 172g.

Expert Rating
3.7
19 reviews
4.4
12 reviews
Screen
6.5" 6.8"
Display
Super AMOLED Dynamic LTPO AMOLED 2X
Resolution
1080 x 2400 1440 x 3120
Pixels Per Inch
405 505
Rear Camera
48 Megapixels 200 Megapixels
Front Camera
32 Megapixels 12 Megapixels
Chipset
Exynos 9611 Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm)
Storage
64GB, 128GB 256GB, 512GB, 1TB
OS
Android Android 15
SIM Type
Nano SIM nano-SIM and e-SIM
Connectivity
Up to 4G Up to 5G
Wi-Fi
802.11 a/b/g/n/ac 802.11 a/b/g/n/ac/6e/7
Bluetooth
5.0 with A2DP, LE 5.3, A2DP, LE
Dimensions
158.5 x 73.6 x 7.9 mm 162.8 x 77.6 x 8.2 mm
Weight
172 grams 219 grams
Water Resistance
Not rated IP68 - Dust and water resistant over 1.5 meter and 30 minutes
Contracts
£29.79/mo (£149.00 upfront)
SIM-free
£124.99 £744.99
Samsung Galaxy A51 Samsung Galaxy A51 Samsung Galaxy S25 Ultra Samsung Galaxy S25 Ultra
Expert Rating 3.7
19 reviews
4.4
12 reviews
Screen 6.5" 6.8"
Display Super AMOLED Dynamic LTPO AMOLED 2X
Resolution 1080 x 2400 1440 x 3120
Pixels Per Inch 405 505
Rear Camera 48 Megapixels 200 Megapixels
Front Camera 32 Megapixels 12 Megapixels
Chipset Exynos 9611 Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm)
Storage 64GB, 128GB 256GB, 512GB, 1TB
OS Android Android 15
SIM Type Nano SIM nano-SIM and e-SIM
Connectivity Up to 4G Up to 5G
Wi-Fi 802.11 a/b/g/n/ac 802.11 a/b/g/n/ac/6e/7
Bluetooth 5.0 with A2DP, LE 5.3, A2DP, LE
Dimensions 158.5 x 73.6 x 7.9 mm 162.8 x 77.6 x 8.2 mm
Weight 172 grams 219 grams
Water Resistance Not rated IP68 - Dust and water resistant over 1.5 meter and 30 minutes
Contracts £29.79/mo
£149.00 upfront
SIM-free £124.99 £744.99
Deals Deals

Frequently Asked Questions

Which has the better screen, the Samsung Galaxy A51 or Samsung Galaxy S25 Ultra?

The Samsung Galaxy S25 Ultra has the bigger screen at 6.8" compared to the Samsung Galaxy A51's 6.5", the Samsung Galaxy S25 Ultra has the sharper display at 505 pixels per inch versus 405, and the Samsung Galaxy A51 uses a Super AMOLED panel while the Samsung Galaxy S25 Ultra has a Dynamic LTPO AMOLED 2X.

Which has the better camera, the Samsung Galaxy A51 or Samsung Galaxy S25 Ultra?

The Samsung Galaxy A51 features a 48 Megapixels rear camera, while the Samsung Galaxy S25 Ultra has a 200 Megapixels rear camera. Both devices also have front-facing cameras for selfies and video calls.

Which is cheaper to buy SIM-free, the Samsung Galaxy A51 or Samsung Galaxy S25 Ultra?

The Samsung Galaxy A51 is cheaper SIM-free, starting from £124.99.

What storage options are available for the Samsung Galaxy A51 and Samsung Galaxy S25 Ultra?

The Samsung Galaxy A51 is available in 64GB, 128GB, while the Samsung Galaxy S25 Ultra comes in 256GB, 512GB, 1TB.

What processors do the Samsung Galaxy A51 and Samsung Galaxy S25 Ultra use?

The Samsung Galaxy A51 is powered by the Exynos 9611, while the Samsung Galaxy S25 Ultra uses the Qualcomm SM8750-AB Snapdragon 8 Elite (3 nm).

Which is easier to carry and hold, the Samsung Galaxy A51 or Samsung Galaxy S25 Ultra?

The Samsung Galaxy A51 is the more portable of the two — it's 47g lighter at 172 grams, it's also the more compact phone at 158.5 x 73.6 x 7.9 mm.

Which is more water resistant, the Samsung Galaxy A51 or Samsung Galaxy S25 Ultra?

The Samsung Galaxy A51 is rated Not rated, while the Samsung Galaxy S25 Ultra is rated IP68 - Dust and water resistant over 1.5 meter and 30 minutes.

What operating system do the Samsung Galaxy A51 and Samsung Galaxy S25 Ultra run?

The Samsung Galaxy A51 runs Android and the Samsung Galaxy S25 Ultra runs Android 15. This is one of the biggest factors when choosing between the two, as each ecosystem has its own apps, services and features.