Samsung Galaxy A51 smartphone: the 2020 vintage has arrived!

Samsung Galaxy A51 smartphone
Samsung Galaxy A51 smartphone

Samsung Galaxy A51 smartphone: the 2020 vintage has arrived!

Samsung Galaxy A51 is the evolution of the A50 and foreshadows the style of other Samsung smartphones in 2020. Its predecessor had hit hard last year, but its versions have struggled to do better. Will this A51 give them new impetus?


Kick off of season 2 of the renew

al of the Galaxy A range. As in April 2019, it is the A5X model (A51 this year) which paves the way for the other versions which will arrive in the year, including the top models of the company’s range, the S20.

Ergonomics and design

The Samsung Galaxy S10 Lite will not be released here. Never mind, the Galaxy A51 takes over the main lines, without really abandoning the design of the Galaxy A range.

Samsung Galaxy A51 smartphone

The format and size are quite similar. The height is the same (158.5 mm). But the A51 is a little less wide (73.6 mm against 74.7 mm) and gains a little in thickness (7.9 mm against 7.7 mm). In fact, regulars of the A50 who would like to change their mobile will not be disoriented. The plastic back cover is adorned with geometric shapes, like what we saw on the Realme 5 and Realme 5 Pro , for example.

At the front, Samsung abandons its Infinity-U panel in favor of the Infinity-O (a notch punched in the center, like on the S10 and Note 10). Gorilla Glass 3 is back to protect the Super Amoled type slab. If the size of the smartphone does not change, its display expands to 6.5 inches. A gain of 0.1 inch which does not really affect usage, but which therefore changes the format (20: 9) and increases the total space occupied by the screen on the front panel, which passes from 85% to 87.8%.


Samsung Galaxy A51 smartphone
Samsung Galaxy A51 smartphone

On this range, Samsung makes the effort to keep the 3.5 mm mini-jack socket which is on the bottom edge, just next to the USB-C port and a speaker. On the right edge, there are the volume and start buttons. On the other side, the microSD card slot and 2 SIM cards. And if there is no mention of the fingerprint reader, it is because, like on the A50, it is located under the Super Amoled panel. And as on its predecessor, it turns out to be a bit finicky in use; nothing insurmountable however.


Like that of the A50, the 3.5 mm mini-jack audio output of the A51 is disappointing. However, the power is sufficient for gourmet headsets, the distortion is controlled and the dynamic range wide. The downside: the stereo reproduction remains of the same ilk as that of the A50. Pity…

Output level181 mVrms97.5 mVrms
Distortion + Noise0.002%0.006%
Dynamic range99 dB96.2 dB
crosstalk-39 dB-60.1 dB


The 6.5-inch screen displays a resolution of 2,400 x 1,080 pixels at a 20: 9 ratio. A slight improvement compared to its predecessor and which allows it to offer a screen of such good quality.

Indeed, with the default parameters (so with the color setting set to “Natural”), we obtain a Delta E of 1.9, with almost no chromatic derivation, except in the green tones which almost reach a value of 8.

The color temperature, measured at 7,031 Kelvin, is a little far from the video standard (6,500 K). It is possible to get a little closer to the reference value by tweaking in the settings, but at the cost of less accurate colors. Thus, by selecting the Vivid parameter and placing the cursor on the right, the color temperature drops below 7000 K, but the Delta E climbs to 5.6.

The display has a very good maximum brightness (555 cd / m²). The reflectance of 48.6% offers good absorption of reflections, for better readability in broad daylight. At night, the minimum brightness of 1.8 cd / m² should not burn your retina.

Finally, the experience is still as fluid, with a tactile delay of 46 ms and an almost non-existent remanence time thanks to the Oled.


The Samsung Galaxy A51 embeds the Exynos 9611 house processor which is an evolution of the Exynos 9610 which was inside the Galaxy A50. A SoC supported this time by 4 GB of RAM.

Unfortunately, it does not shine as much with its performance. It obtains an overall index of 68.95, far from the Huawei Nova 5T for example (92.31). In multitasking, its score of 89.24 is a little bit better than that of the A50 (88.37), but still far from that of the Mi 9T Pro (98.03) or Nova 5T (95.11).

For gaming, the smartphone uses the same graphics chip as the A50, but offers much lower performance. Optimization does not seem to have been the priority of the brand and it is a shame. However, most games run with no big visible problem, except for the headlines. An evil recovered from its predecessor.

Our performance tests are carried out with viSer, the application developed by the company Smart Viser.


Like the majority of smartphones in recent months, the A51 opts for a composition of 4 photo sensors on the back, arranged like this:

Main module: 48 megapixels, f / 2, eq. 25 mm

As this is only the second smartphone from Samsung to offer a 48 megapixel sensor, we wanted to subject it to a small comparison against the Galaxy A80 (the first 48 megapixel of the brand). This test carried out as a preamble to this test can be found in our laboratory article: