Redmi K90 vs Samsung Galaxy A21s

The Redmi K90 (2025) runs on the Qualcomm Snapdragon 8 Elite, while the Samsung Galaxy A21s (2020) runs on the Exynos 850; launch prices were $401 and $215. By overall MobileRank rating, the Redmi K90 leads — 76/100 vs 29/100 (a 47-point difference). Key differences: the Redmi K90 has the bigger battery (7100 mAh vs 5000); the main camera is 50 MP vs 48 MP; the Redmi K90 is faster in AnTuTu (3,077,585 vs 234,339).

The Redmi K90 significantly outperforms the Samsung Galaxy A21s by 47 points (76/100 vs 29/100).

Profile comparison

Category scores

Redmi K90

Performance 91
Display 82
Camera 58
Battery 72
Portability 55
Value for money 80

Samsung Galaxy A21s

Performance 16
Display 32
Camera 30
Battery 52
Portability 55
Value for money 16

What makes Redmi K90 better?

  • Higher AnTuTu: 3077585 vs 234339
  • Better Geekbench Single: 3013 vs 300
  • Better Geekbench Multi: 9287 vs 836
  • Bigger battery: 7100 vs 5000 mAh
  • Better main camera: 50MP vs 48MP
  • Higher refresh rate: 120Hz vs 60Hz

  • Higher performance (91/100 vs 16/100)
  • Better camera (58/100 vs 30/100)
  • Longer battery life (72/100 vs 52/100)
  • Better display (82/100 vs 32/100)

What makes Samsung Galaxy A21s better?

  • Lighter: 192g vs 206g
  • Cheaper at launch: $215 vs $401

  • Overall rating 29/100

Comparison verdict

Comparing the Redmi K90 vs the Samsung Galaxy A21s, the Redmi K90 scores 47 points higher (76/100 vs 29/100). In the "performance" category, the Redmi K90 leads (91/100 vs 16/100). In the "camera" category, the Redmi K90 leads (58/100 vs 30/100). In the "battery" category, the Redmi K90 leads (72/100 vs 52/100). Value score: Redmi K90 — 80/100, Samsung Galaxy A21s — 16/100; it shows how far a model sits above or below the usual level for its price, and is not part of the overall rating. In the "performance" category, the Redmi K90 significantly outperforms the Samsung Galaxy A21s (91/100 vs 16/100). In the "display" category, the Redmi K90 significantly outperforms the Samsung Galaxy A21s (82/100 vs 32/100). In the "camera" category, the Redmi K90 notably outperforms the Samsung Galaxy A21s (58/100 vs 30/100). In the "battery" category, the Redmi K90 notably outperforms the Samsung Galaxy A21s (72/100 vs 52/100). In the "portability" category, both devices are on the same level — 55/100.

Redmi K90: The Redmi K90 is a better fit for gamers and power users, budget-conscious buyers.

Specs comparison

Specification Redmi K90 Samsung Galaxy A21s
Processor Qualcomm Snapdragon 8 Elite Exynos 850
AnTuTu 3077585 234339
Geekbench Single 3013 300
Geekbench Multi 9287 836
Display 6.6" AMOLED 6.5" IPS LCD
Resolution 2510x1156 —
Refresh rate 120 Hz 60 Hz
Battery 7100 mAh 5000 mAh
Charging 100W —
Main camera 50 MP 48 MP
Ultrawide 8 MP 0 MP
Telephoto 50 MP 0 MP
Front camera 20 MP 13 MP
RAM 12GB / 16GB 3GB / 4GB / 6GB
Storage 256GB / 512GB 32GB / 64GB
OS Android 16 —
Brightness (peak) 3500 nits —
NFC yes yes
Protection IP68 —
Dimensions 157.5×75.3×8.0 mm 163.7×75.3×8.9 mm
Weight 206 g 192 g
Launch price $401 $215

Camera comparison

Redmi K90

  • Main: 50MP f/1.9
  • Ultrawide: 8MP
  • Telephoto: 50MP
  • Front: 20MP
58
camera

Samsung Galaxy A21s

  • Main: 48MP
  • Front: 13MP
30
camera

Display comparison

Redmi K90

  • 6.6" AMOLED
  • Resolution: 2510x1156
  • Refresh rate: 120 Hz
82
display

Samsung Galaxy A21s

  • 6.5" IPS LCD
  • Refresh rate: 60 Hz
32
display

Battery and charging

Redmi K90

  • 7100 mAh
  • Wired: 100W
  • No wireless charging
72
battery

Samsung Galaxy A21s

  • 5000 mAh
  • No wireless charging
52
battery

Overall performance score

We compared Redmi K90 and Samsung Galaxy A21s, covering their specs and all relevant benchmarks.

Redmi K90 Qualcomm Snapdragon 8 Elite
76/100
3077585 AnTuTu
Samsung Galaxy A21s Exynos 850
29/100 -1213.3%
234339 AnTuTu

Redmi K90 leads Samsung Galaxy A21s by 1213.3% in our overall performance rating.

Benchmarks

Launch prices and where to check today's

Redmi K90

$401

Samsung Galaxy A21s

$215

Launch price difference: $186. Samsung Galaxy A21s was $186 cheaper at launch.

Detailed category analysis

performance

In the "performance" category, the Redmi K90 significantly outperforms the Samsung Galaxy A21s (91/100 vs 16/100).

display

In the "display" category, the Redmi K90 significantly outperforms the Samsung Galaxy A21s (82/100 vs 32/100).

camera

In the "camera" category, the Redmi K90 notably outperforms the Samsung Galaxy A21s (58/100 vs 30/100).

battery

In the "battery" category, the Redmi K90 notably outperforms the Samsung Galaxy A21s (72/100 vs 52/100).

portability

In the "portability" category, both devices are on the same level — 55/100.

Frequently asked questions

Which is better: the Redmi K90 or the Samsung Galaxy A21s?

The Redmi K90 significantly outperforms the Samsung Galaxy A21s by 47 points (76/100 vs 29/100).

What is the rating of the Redmi K90 and the Samsung Galaxy A21s?

The Redmi K90 has a MobileRank rating of 76/100, the Samsung Galaxy A21s — 29/100.

Which has the better camera: the Redmi K90 or the Samsung Galaxy A21s?

The Redmi K90 leads on camera score (58/100 vs 30/100).

Which is more powerful: the Redmi K90 or the Samsung Galaxy A21s?

The Redmi K90 leads on performance (91/100 vs 16/100).

Should you choose the Redmi K90 over the Samsung Galaxy A21s?

The Redmi K90 is a better fit for gamers and power users, budget-conscious buyers.