Home : Smartphones

Samsung Galaxy S21 Plus vs OnePlus 9: Which to Pick?

author Luis Silva (July 2021 Updated: March 2022 - 6 min. reading time)

The Galaxy S21 Plus isn't that affordable, but it also is the better device of the two considering their specs.

You'll get better glass protection and a better display.

What else stands out?

With the Galaxy S21 Plus, you'll also get a larger (+0.2") display, optical image stabilization, and reverse wireless charging. But with the 9, you can get faster-charging speeds (65w vs. 25w) and Bluetooth 5.2.

But how much more will I have to pay for the Galaxy S21 Plus?

If you're going off-contract, you'll have to invest an additional amount close to $278.

Is it worth getting the Galaxy S21 Plus in 2022?

The Samsung Galaxy S21 Plus is clearly worth buying in 2022, even if there are better phones out there. Sure, you can take a peek at other devices like the 9 Pro, but this one does hold a good performance, good battery life, excellent glass protection, and 8K recordings.

Is the 9 still worth buying in 2022?

Of course, I still recommend the 9 in 2022. Its overall score hasn't dropped much yet, mainly because of its good performance, good battery life, fast charging, and 8K recordings. It doesn't mean you can't take a quick peek at (again) the 9 Pro, though.

Keep reading for answers to all your questions about their differences, how they rival their competition, and you'll know what the industry thinks about their specs.

Check prices on Amazon Check prices on Amazon
Click here or scroll down to check prices on eBay, BestBuy, and Walmart.

I earn a small fee from qualifying purchases. It doesn't affect the price you pay nor my opinions.

Samsung Galaxy S21 PlusOnePlus 9


Click on one of these
shortcuts and then tap
"back" to return here


In March of 2021, OnePlus started selling its 9, while Samsung's Galaxy S21 Plus hit the stores in January 2021.

Here you can look at the Galaxy S21 Plus and the 9, compare each other's features, and decide which one is best for you. Let us delve into the finer details.

The weight of each section

For additional information regarding our smartphone comparisons, check this FAQ.

to check who their rivals are.

Device Galaxy S21 Plus 9
Release Date 2021, January 2021, March 0y.
OS Updates 3 years 2 years -1y.
Security Updates 4 years 3 years -1y.

*Reference: 100: Apple iPhone 13 Pro Max.

Which One Has The Best Performance?

As for performance, Geekbench 5 scores the 9 9% ahead of its competitor in the multi-core ranking. On daily usage, you wouldn't be able to notice any relevant differences between them.

Are you looking for the quickest phone around? The 9 is clearly above the average if you consider its rivals. While the average sits at 2442, this one is 39% above them.

It's safe to say that both of them can be tagged as high-end.

Features Galaxy S21 Plus 9
SoC Exynos 2100 Snapdragon 888
Graphics Mali-G78 MP14 Adreno 660
Geekbench 5 Score 3113
OS Android 11 and OneUI Android 11 and OxygenOS 11

*Reference: 100: Apple iPhone 13.

Which Phone Has The Best Display?

Samsung Galaxy S21 Plus front transparent png OnePlus 9 front transparent png

There's no phone to praise here, so don't worry about it. But the Galaxy S21 Plus features better glass protection.

If you're leaning towards the Galaxy S21 Plus, 84% of its rivals can play HDR content and have an Always-On display, and all have an AMOLED screen.

Compared to the 9, I should say that 83% of its rivals can play HDR content, 96% have an AMOLED screen, and 87% have an Always-On display.

Display Density (DPIs)*
Features Galaxy S21 Plus 9
Size 6.7
Resolution (px) 1080x2400
Refresh Rate 120hz 120hz 0
Dots per Inch 392.81
Always-On-Display Yes Yes
Notch Hole Hole
Peak Brightness 883 nits
821 nits
Sub Tek-Score
Protection Corning Gorilla Glass Victus Corning Gorilla Glass 5

*Reference: 100: Sony Xperia 1 II.

Which Phone Has The Best Cameras?

Samsung Galaxy S21 Plus back transparent png OnePlus 9 back transparent png

If you value quality photos, you should know that the 9 is about 63% above its adversaries in its class. But you won't find a winner here.

About the Galaxy S21 Plus: DXOMARK tested this camera and gave it a score of 123. By including its wide-angle lens, the final score goes up to 137 points. If you click here, you can check what they think of it.

Before moving on, keep in mind that all of its rivals can record videos in 4K or more and have an ultra-wide-angle lens, and 92% feature Optical Image Stabilization. Although only 20% of them feature a macro lens.

About the 9: DXOMARK evaluated this camera, and here's the score: 123. And if we consider its wide-angle lens, this score goes up to 131 points. Just click here to read about it.

Finally, if you must know, all of its rivals can record videos in 4 or 8K and have an ultra-wide-angle lens, and 96% feature Optical Image Stabilization. Additionally, only 22% of them feature a macro lens.

If you're not a numbers person, we can tag these two as high-end.

If you take optical zoom seriously, just ignore these two and check the 9 Pro instead. And if you're willing to take it one step further, smartphones like the Galaxy S20 Ultra are much more fun.

Picture Quality*
Primary Camera Galaxy S21 Plus 9
Megapixels 12
Aperture 1.8
Lens 26mm
Lens Type Wide-Angle Wide-Angle
Flash 1 2 1
HDR Yes Yes
OIS Yes No
Video 4320 4320 0
Score 137

*Reference: 100: Xiaomi Mi 11 Ultra.

Extra Camera(s) Galaxy S21 Plus 9 vs.
Megapixels 64
Aperture 2.0
Lens 29mm 14mm -15
Lens Type Regular Ultra-wide-Angle
Megapixels 12 2 -10
Aperture 2.2 2.4 0.2
Lens 13mm -
Lens Type Ultra-wide-Angle -
Score 14 8 -6
Selfie Camera Galaxy S21 Plus 9 vs.
Megapixels 10
Aperture 2.2
Lens 26mm -
Galaxy S21 Plus 9 vs.

Who has the best frame?

They ended up with the same score, so don't worry too much.

The Galaxy S21 Plus is a little bit heavier: About 8 g. (0.28 oz). If you're curious, I've come up with an adapted "display size to phone weight ratio" score. The Galaxy S21 Plus got 4.6, and that's another way of saying it has an acceptable score for its screen size. The 9, on the other hand, has 4.8, so nothing to state here.

The Galaxy S21 Plus is resistant to water up to 1 to 3 meters, on par with the 9. That should be for up to 30 minutes, in standby mode, so no underwater photos.

Body Galaxy S21 Plus 9
Size 161 x 75 x 7 mm
(5.68 x 2.65 x 0.25 in)
160 x 74 x 8 mm
(5.64 x 2.61 x 0.28 in)
Weight 200 g. (7.05 oz)
192 g. (6.77 oz)
Build Front and back glass Front and back glass
Colors Phantom Black, Phantom Violet, Phantom Silver, Phantom Red, Phantom Gold, and Phantom Pink Winter Mist, Astral Black, and Arctic Sky
Screen To Body Ratio 89.75%
Disp.Size To Weight Score 4.6 4.8 0.2
Looks 10.0/10
Waterproof IP68 IP68 (T-Mobile variant only)
Biometrics Under Display Fingerprint Under Display Fingerprint

*100% = 4+ colors + front and back glass + S2BR: 86+%.

Which has the best battery?

The Galaxy S21 Plus has a 4800 mAh battery, and the 9 has a 4500 mAh. And GSMArena did test them out, and the former does have better battery life.

For the record, the Galaxy S21 Plus is also beating most smartphones. Actually, it may even be on our top 10 list with the best battery life.

The 9 does charge quicker. Its competitors usually stay at around 29w/hour.

Features Galaxy S21 Plus 9
Capacity (mAh) 4800 4500 -300
1h Talk + 1h Web + 1h Video 84% left
82% left
1h Talk + 3h Web + 1h Video 70% left
67% left
1h Talk + 1h Web + 3h Video 74% left
69% left
Bat. To Phone Size Score 3.6 3.5 -0.1
Sub Tek-Score
Fast Charging 25w
Wireless Charging 15w
Reverse Charging 4.5w
No -4.5

*Reference: 90: Samsung Galaxy A42.

Which has more storage?

There isn't a winner here.

Features Galaxy S21 Plus 9
Internal (GB) 128GB
Micro SD No No

*Internal Storage + 256GB Memory Card (Max: 512GB).

Which is the most connectivity-friendly?

The 9 is your better option, as it features Bluetooth 5.2.

If you love good-old wired headphones, you're out of luck because none of them included a 3.5mm headphone jack. Want a piece of advice? Forget about adapters and go for the wireless buds. There also are other options out there if you're not really leaning towards any of these. Perhaps you don't mind settling with the Galaxy Note 10 Lite.

The 9 has two network variants: LTE or (LTE and) 5G.

Features Galaxy S21 Plus 9
Network 5G 5G (also available in LTE)
Bluetooth 5.0
NFC Yes Yes
3.5mm jack No No

Which is more affordable?

Here are the best deals on some major online stores:

Samsung Galaxy S21 Plus

Reference: $999

Samsung Galaxy S21 Plus

OnePlus 9

Reference: $721

OnePlus 9

I earn a small fee from qualifying purchases. It doesn't affect the price you pay nor my opinions, but it will mean a lot if you click on one of these buttons before purchasing your next phone (or whatever else you end up buying). You'll be helping to take this to the next level.

Prices on eBay are in $US but Europe-based. You can click to check the prices in your country.

Prices marked with ! are from renewed/refurbished/carrier-locked phones (except eBay prices that, as a last resort, can be from bids or used devices).

How much of a "phone" can your money buy?
That's how much "score" you can get with $100 based on the global score that you'll see in the next section (higher is better).

Have you found better prices elsewhere? The formula is simple: score/price*100.

Value for money Galaxy S21 Plus 9 VS
Amazon - - -
eBay 1.15 1.33 0.18
Best Buy - - -
Walmart - - -

Also, don't forget to check the latest deals from these four stores, and the state of the art on mobile technology, if you don't want to overpay on your next smartphone.

Related articles:

Best smartphone deals

The Best Unbiased Smartphones For All Budgets

Smartphone Specs Statistics: The State Of The Art (Q1 2021)

Are you also considering other options? The global score can help. But first, let's see where its rivals are. They usually sit close to 6.9 (for the Galaxy S21 Plus) and 6.7 (for the 9).

Verdict: What Makes the Samsung Galaxy S21 Plus Stand Out?

What can the Samsung Galaxy S21 Plus give you that the OnePlus 9 can't:

- Better glass protection

- Better display

- A larger display (+0.2")


- Reverse wireless charging

What can the OnePlus 9 give you that the Samsung Galaxy S21 Plus can't:

- Faster charging speeds (65w vs. 25w)

- Bluetooth 5.2

Pros Galaxy S21 Plus 9
#1 Performance Performance
#3 Always-On-Display Always-On-Display
#4 Cameras Cameras
#5 Battery Life Fast Charging
#6 Fast Charging Wireless Charging
#7 Wireless Charging
#8 Glass Protection
Cons Galaxy S21 Plus 9
#1 MicroSD Slot MicroSD Slot
#2 Weight Weight
#3 3.5mm Jack 3.5mm Jack
#4 Price Price
Relative Score*
Global Score Galaxy S21 Plus 9
Gaming Score
Your Score

*Reference: 100: Samsung Galaxy Note 20 Ultra.

Scroll the sliders down below to get your own personalized score. Let's suppose you value performance and battery life, and you don't really care about anything else. Then, just set the "Performance" and the "Battery" sliders up to 5 (5+5=10), and then the other sliders down to 0. You'll know what's the best phone for you.

Performance 1.9
Display 1.7
Cameras 1.4
Frame 0.9
Battery 1.9
Storage 2.0
Connectivity 0.4
Total Should be 10 or as close as possible: 9.6

For suggestions and bug reports, click here. Your help is appreciated. Thank you.

If you want to know more about them, click here:

About me


My name is Luis Silva, and I have a degree in computer management. Ever since I was a teenager, I've loved everything to do with tech. Music, pictures, video editing, I've done it all! This site is a place for me to share some of the knowledge I have, as well as keep up-to-date with current trends. This is a wonderful place for tech-geeks and everyone else that just want to learn more about tech and smartphones in general.

Keep in touch

pinterest logo Follow us on Pinterest

facebook logo Join our Facebook group

No spam, I promise. You can unsubscribe at any time and I'll never share your email without your permission.

Samsung Galaxy S21 Plus Related Comparisons

OnePlus 9 Related Comparisons


"Display size to phone weight" ratio explained

This indeed is a "display size to phone weight" ratio, but because every phone ended up somewhere between 0.0272 and 0.0421, I've amplified (adapted) those values so they would fit in a 0-10 scale. As of now, the best smartphone is the Samsung Galaxy A40, with 140g. (4.94 oz) for a 5.9 inch display. It got a score of 9.92. While the worse device is the iPhone 8 Plus, which weighs 202 g. (7.13 oz) and has a 5.5-inch display. It ended up with a score of 0.75.

Please, be aware that this score is subject to change if and when a new smartphone comes along that ends up being outside of this scale.


"Battery to device size" ratio explained

This score should give you an idea about the energy footprint of the devices you're considering. It reflects not only the hardware and the energy that it requires but also the amount of energy that the battery can deliver.

The major spenders on any device should be the display and the SoC. But everything from a notification led to its modems need to be optimized, or else, the OEM should simply include a bigger battery as a compensation. Unfortunately, it isn't always possible due to size limitations. But in the end, if a particular OEM can do a good job and give you excellent battery life on a small device, so should everyone else. That's why I've added a "battery to device size" ratio. But since the real scale went from 119 (for the Galaxy S10e, Snapdragon variant) and up to 164 (for the iPhone 7 Plus), I've decided to convert them so they would fit in a 0-10 scale, being 0 the worst device, (the iPhone 7 Plus) and 10 the one every OEM should look up to.

As an example, Apple did an excellent job on the iPhone 7. It has a score of 8. Despite having a small capacity, the hardware is well optimized, and it still gives you decent battery life considering its size. The iPhone 7 Plus, on the other hand, with those bezels shrinking its display size, clearly could've been the #1 in our top 10 list of best battery devices if Apple simply filled all that empty space with a bigger battery.

As a side note: I haven't included the dept of the devices in this formula because even if a device ended up being 1mm/0.03 inches thicker, it wouldn't matter that much to those who really value battery life.

Please, be aware that this score is subject to change if and when a new smartphone comes along that ends up being outside of this scale.



As of now, these are the rivals that were considered for each of them. They may change every time its prices are updated.

These are the lowest prices found on Amazon, eBay, BestBuy, and Walmart.

 Samsung Galaxy S21 Plus 
  • ApplerivaliPhone 12
  • SonyrivalXperia 5
  • ApplerivaliPhone X
  • SamsungrivalGalaxy Note 9
  • ApplerivaliPhone 11 Pro
  • ApplerivaliPhone XS Max
  • ApplerivaliPhone 11 Pro Max
  • SamsungrivalGalaxy S10 Plus
  • SamsungrivalGalaxy S10+ EX
  • SamsungrivalGalaxy S10+ SD
  • SamsungrivalGalaxy S20 EX
  • OnePlusrival7T Pro
  • HuaweirivalP30 Pro
  • SamsungrivalGalaxy S20
  • SamsungrivalGalaxy S20 Plus
  • HuaweirivalP40
  • OnePlusrival8
  • XiaomirivalMi 10 Pro
  • OpporivalFind X2 Neo
  • ApplerivaliPhone 12 Mini
  • SamsungrivalGalaxy S21
  • OnePlusrival8T
  • XiaomirivalMi 10
  • OpporivalReno4 Pro
  • XiaomirivalMi 11
  • OnePlusrival9 Pro
  • OnePlusrival9
  • OpporivalFind X3 Lite
  • ApplerivaliPhone 13 Mini

 OnePlus 9 
  • SonyrivalXperia 1
  • ApplerivaliPhone X
  • ApplerivaliPhone 11
  • SamsungrivalGalaxy Note 9
  • ApplerivaliPhone 11 Pro
  • SamsungrivalGalaxy S10e
  • SamsungrivalGalaxy S10
  • SamsungrivalGalaxy S10e SD
  • SamsungrivalGalaxy S10+ SD
  • SamsungrivalGalaxy S10 EX
  • SamsungrivalGalaxy S10 SD
  • OnePlusrival7 Pro
  • OnePlusrival7T Pro
  • HuaweirivalMate 20 Pro
  • OnePlusrival8
  • XiaomirivalMi 10 Pro
  • SamsungrivalGalaxy Note 10 Lite
  • SamsungrivalGalaxy S20 FE 4G
  • OpporivalFind X2 Neo
  • GooglerivalPixel 5
  • SamsungrivalGalaxy S21
  • XiaomirivalMi 10T Pro
  • XiaomirivalMi 10
  • OpporivalReno4 Pro
  • SamsungrivalGalaxy A72
  • OpporivalFind X3 Lite
  • OnePlusrivalNord 2

Formula deviation

Since the guys at DxoMark don't review every camera out there, I've come up with a formula based on the ones that they do rate, so I could get an equivalent score for the ones they don't review. After testing it against these cameras, I got the deviation between that and their DxO score.

Device: DxOScore Deviation
Samsung Galaxy A50: 88 -1
Apple iPhone XR: 104 1
Xiaomi Mi 9T Pro: 108 -7
Xiaomi Redmi Note 8 Pro: 87 1
Sony Xperia 1: 99 -1
Sony Xperia 5: 101 1
Samsung Galaxy Note 8: 100 0
Samsung Galaxy Note 10 Plus: 126 2
Apple iPhone 8 Plus: 96 -3
Xiaomi Pocophone F1: 92 -1
Apple iPhone 7 Plus: 90 -1
Apple iPhone X: 101 3
Apple iPhone 11: 112 -1
Samsung Galaxy Note 8: 100 0
Samsung Galaxy Note 9: 107 1
Apple iPhone XS Max: 110 -2
Apple iPhone 11 Pro Max: 124 1
Samsung Galaxy S10: 124 2
Apple iPhone XS: 110 -1
Samsung Galaxy S10 Plus: 120 -2
OnePlus 7 Pro: 122 0
OnePlus 7T Pro: 122 0
Huawei P30 Pro: 125 -1
Google Pixel 4: 117 0
Google Pixel 3: 103 0
Google Pixel 2: 100 0
Samsung Galaxy S20 Plus: 127 -2
Samsung Galaxy S20 Ultra: 132 2
OnePlus 6: 100 0
OnePlus 6T: 101 1
Samsung Galaxy S9 Plus: 105 -1
Huawei Mate 20 Pro: 120 0
Xiaomi Mi 9: 115 0
Huawei Mate 30 Pro: 132 0
Huawei P40 Pro: 140 -1
Apple iPhone SE 2: 101 0
OnePlus 8 Pro: 126 0
Xiaomi Mi 8: 105 1
Samsung Galaxy A71: 89 1
Xiaomi Mi 10 Pro: 134 0

As you can see, most cameras sit between 1 and -1, while a few of them go up to 2 or -2. That means it's reasonable to assume other similar cameras that they don't review to, in the worst-case scenario, be anywhere from -2 to 2 points from the score that the formula gets.

For example: Given that the Pixel 4 got 117 points and that the Pixel 4 XL share the same year and camera specs, it's reasonable to expect a score of 117 too. But in reality, if they do review that camera, it may end up anywhere between 115 and 119.

Be aware that at DxO, they give a score based on their opinion, not based on any formula. That's why I think there's an odd difference of 6 points between the iPhone 8 Plus and the iPhone X. In theory, they should have the same camera.

I'm guessing that the Mi 9T Pro got a deviation of 7 points because they tested its Chinese variant (the K20 Pro).

Update: They just changed their protocol to include preview image evaluation and trustability. I'm keeping the old table (for now) for reference purposes, and I'll be adding a new one as soon as they review at least a couple of new mclass-range cameras.

You can expect the same (or a bit bigger) deviation for high-end cameras, but anything with a score below 100-110 should be taken with a grain of salt.

This is valid for all cameras tested with the previous protocol. For those that they dclassn't test, the deviation may be up to twice as much.


About GeekBench 5

This is just a quick note to let you know that, if, by any chance, the smartphone you're looking for isn't on the GeekBench site yet, you can check on GsmArena.com, as they also usually test smartphones with that benchmark tool.

Top 10 Smartphones