Samsung Galaxy S21 vs Samsung Galaxy S20: How do the two phones compare?

Samsung has announced three new versions of the Samsung Galaxy S21: the S21 itself, the S21 Plus and the S21 Ultra. The standard 5G S21 is the phone we think most people will be interested in – so how does it compare to the current Samsung Galaxy S20 5G?

The first and most obvious difference is that it's an awful lot cheaper. Samsung has slashed the price of the entire Galaxy S21 range by $200.

There are some really worthwhile improvements here, but there are some less welcome changes too. As you'd expect, the 2021 Samsung Galaxy S21 boasts a vastly improved processor and a better graphics processor too, and it comes with an alphabet soup of 5G and LTE and Wi-Fi up to 802.11 6E. But the standard Galaxy also gets a lower resolution screen than last year, and while the range-topping Ultra gets a superb new set of cameras, the S21 has the same cameras as last year's models – although there are some important changes to the camera software.

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That makes this comparison particularly interesting because inevitably, the S20 is going to start getting deeper discounts now that the new model is here. The S21 is better than the S20 in lots of ways, not least its price tag. But will it be a better buy than a heavily discounted S20? Let's find out. 

Samsung Galaxy S21: Video

Before we get stuck into the comparison between the Samsung Galaxy S21 vs Samsung Galaxy S20, here's a detailed overview video that walks you through each model in the new Galaxy S21 range.

Samsung Galaxy S21 vs Samsung Galaxy S20: design

There's not a huge difference in the appearance of these two phones: Samsung's design language for its Samsung Galaxy devices is well established now, and with the exception of the S21's new camera housing there's very little visual difference between the 2020 and 2021 phones. There are still some differences, however, and the most obvious one is that where the Galaxy S20 has a glass back the S21 has a plastic one. The more expensive S21+ and S21 Ultra get aluminium.

The standard Galaxy S21 comes in four colours: pink, violet, white and grey.

Both the Galaxy S20 and the Galaxy S21 offer an almost bezel-free edge to edge Infinity display and have a slightly protruding rear camera block in the upper left hand corner of the case. The S21's camera block is slightly taller and Samsung has made some interesting and we think attractive colour contrasts between it and the rest of the case.

The front camera is embedded in the display thanks to a centred hole-punch design: when the display shows a light colour you can see the dot in the top centre where the selfie camera lives, but it takes a fraction of the screen space that the notch in an iPhone does.

Although you can't see it, the fingerprint sensor is 1.7x larger than before to deliver easier and faster unlocking and authentication.

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Samsung Galaxy S21 vs Samsung Galaxy S20: display

The Galaxy S20 display was, and is, great. It's a 6.2-inch Quad HD+ AMOLED delivering 3,200 x 1,440 pixels at 563ppi. It’s HDR10+ certified and supports refresh rates up to 120Hz. It's a really great screen, so we can understand why some Samsung fans are disappointed by the specs for the new Samsung S21: while the screen is the same size, supports HDR10+ and has a 120Hz refresh rate the pixel density is considerably lower. 

The display in the Samsung Galaxy S20 is 564ppi, with a resolution of 1,440 x 3,200 pixels. But the display in the Samsung Galaxy S21 is 421ppi and delivers 1,080 x 2,400: FHD+ rather than Quad HD+.

Does it matter? FHD+ displays are crisp and clear and many rival flagships run at that resolution too, so Samsung's hardly stripping out a brilliant screen and replacing it with a clunker from 2012. While some people will be disappointed to see the specification take what appears to be a backwards step, we think more people will be delighted that the phone is $200 cheaper.

Samsung Galaxy S21 vs Samsung Galaxy S20: processor, memory, OS and storage

The Galaxy S20 is powered by a Snapdragon 865 in the US or a Samsung Exynos 990 in the rest of the world. Whichever processor you get, its’ backed with 8GB of RAM (12GB in the 5G model) and 128GB of internal storage. It has a microSDXC card slot but the S21 does not.

The Galaxy S21 gets the more powerful Snapdragon 888 in the US, China and Korea and Samsung’s new Exynos 2100 everywhere else. Once again there’s 8GB of RAM and a choice of 128GB or 256GB of internal storage. According to Samsung this new Exynos and its accompanying GPU deliver over 30% better performance and 40% better graphics performance. The Snapdragon delivers 20% faster CPU performance than before and 25% faster graphics.

The Samsung Galaxy S21 runs Android 11 with One UI 3.1; the S20 had Android 10 and One UI 2.5.

Samsung Galaxy S21 vs Samsung Galaxy S20: cameras

If you were hoping that upgrading from the S20 to the S21 would mean upgrading all the cameras, we're sorry to disappoint: the S21 has the same three camera setup as before. The only Galaxy that's getting a big camera upgrade so far is the S21 Ultra, whose four-camera setup includes a 108MP sensor.

The S21's camera system may not be different from the one in the Galaxy S20, but it's still a superb system – and it's still better than many rivals. It's a 64MP+12MP+12MP (telephoto, wide-angle and ultra-wide respectively) with 3x hybrid zoom, 30x digital zoom and optical image stabilisation (OIS). The 64MP camera has a f/2.0 aperture, the wide-angle f/1.8 and the ultra-wide has an aperture of f/2.2. Storage permitting, the Galaxy S20 can shoot video at up to 8K. The selfie camera is 10MP with a f/2.2 aperture.

There are some big changes in the camera software. The new Director View enables you to record video using your front and rear cameras simultaneously, displaying live thumbnails for each lens so you can see what your phone is seeing, and Single Take 2.0 makes it easy to capture with multiple cameras simultaneously to create effects such as dynamic slow-mo.

Samsung Galaxy S21 vs Samsung Galaxy S20: battery and charging

These are big phones and they have big batteries to match. The S21 follows in its predecessor's footprints with a large 4,000mAh battery; as before the Plus and Ultra models get even bigger batteries to go with their larger screens.

Both the Galaxy S20 and the Galaxy S21 support fast charging at 25W, wireless charging at 15W, reverse wireless charging at 4.5W and USB Power Delivery. 

Last month, Samsung was spotted deleting a recent Facebook advert that mocked Apple for not including a charger with the iPhone 12. Now we know why: the Samsung Galaxy S21 doesn't come with a charger either. But unlike Apple, Samsung owners aren't going to need to buy a new one to match a new kind of cable: if you're upgrading from the Galaxy S20 you can use your new phone with your existing charger.

Samsung says while the battery is the same as before, the S21 should deliver better battery life thanks to its more efficient processor and its AI-powered energy saving.

Samsung Galaxy S21 vs Samsung Galaxy S20: first impressions

There are lots of reasons to like the Samsung Galaxy S21. 

It's one of the most advanced Samsung Galaxy smartphones we've ever seen. It has a much more powerful processor, dramatically improved graphics performance, the latest 5G tech and a newer version of Android. You can specify it with more internal storage too. It's $200 cheaper. And it's a good-looking thing, svelte, sleek and expensive-looking. If you're coming to the S21 from rivals, or from a Galaxy from 2019 or before, you're going to love it.

But in this feature we're comparing the S21 with the S20, and not all of the comparisons are so positive. Swapping glass for plastic is clearly a cost-cutting move, but it makes the phone look and feel that little bit less premium. The cameras aren't better than last year, although the software has been improved. There's no microSD slot. And the display, while perfectly good, is lower resolution than last year's model. We suspect we'll see a fair bit of online criticism of that in the coming weeks – and lots of Samsung Galaxy S20 deals too.

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