Home Phone comparison Samsung Galaxy S25 Plus and Samsung Galaxy S21 Ultra - Which is better?

Samsung Galaxy S25 Plus vs Samsung Galaxy S21 Ultra

91 out 100
Samsung Galaxy S25 Plus
VS
67 out 100
Samsung Galaxy S21 Ultra
Samsung Galaxy S25 Plus
Samsung Galaxy S21 Ultra

Compared 2 smartphones : Samsung Galaxy S25 Plus Manufactured in February, 2025, with display 6.7 with chipsetQualcomm Snapdragon 8 Elite, vs Samsung Galaxy S21 Ultra, Manufactured in February, 2021with chipsetSamsung Exynos 2100. Below are specs, tests, pros and cons for each device

  1. Differences
  2. Review
  3. Specs
  4. Benchmarks
  5. Battery Life
  6. Cameras
  7. Comments (0)

Key Differences

Device key advantages
Reasons to choose Samsung Galaxy S25 Plus
  • Lighter design: 190g vs 227g
  • Newer Bluetooth version: 5.4 vs 5.2
  • Supports DisplayPort
Reasons to choose Samsung Galaxy S21 Ultra
  • Larger display: 6.8in
  • Higher pixel density: 515ppi
  • Higher battery capacity: 5000mAh vs 4900mAh

Versions

Available versions and configurations
Memory Options - 12/256 GB
- 12/512 GB		 - 12/128 GB
- 12/256 GB
- 12/512 GB
- 16/256 GB
- 16/512 GB

Review

Key Specs Samsung Galaxy S25 Plus and Samsung Galaxy S21 Ultra
Display
Color accuracy, sharpness & brightness
Camera
Main & front camera tests
Performance
App & system performance
Games
3D gaming performance
Battery
Battery life, charging speed & type
Connectivity
Connectivity features
NanoReview Score
Overall score by NanoReview
Adjust each parameter’s importance to find the best match for you.
Customize your score
Function
Importance (Weight)
Display:
Camera:
Performance:
Gaming:
Battery:
Connectivity:
Higher weight means greater impact on NanoReview score.

Tests & specs

Specs & test comparison
Smartphones:
Samsung Galaxy S25 Plus
vs
Galaxy S21 Ultra

Display

Display quality comparison
Type Dynamic AMOLED Dynamic AMOLED
Size 6.7 in 6.8 in
Resolution 1440x3120 pixels 1440x3200 pixels
Aspect ratio 19.5:9 20:9
Pixel density 513 ppi 515 ppi
Refresh rate 120 Hz 120 Hz
Adaptive refresh rate Yes (1-120 Hz) Yes (10-120 Hz)
Max brightness 2600 nits 1500 nits
HDR support Yes HDR10+ Yes HDR10+
Touch Sampling Rate 240 Hz n/a
Screen-to-body ratio 91.7 % 89.5 %
Features - DCI-P3
- Always-On Display		 - DCI-P3
- Always-On Display
Display test
Peak brightness (auto)
Samsung Galaxy S25 Plus
1444 nits
Samsung Galaxy S21 Ultra
1019 nits
sRGB gamut96.8 %n/a
PWM (Flicker)240 Hzn/a
Response time1 msn/a
Contrast∞ Infiniten/a
Sources: NotebookCheck [Samsung Galaxy S25 Plus], [Samsung Galaxy S21 Ultra]

Design & Build

Design and ergonomics comparison
Height 158.4 mm (6.24 in) 165.1 mm (6.5 in)
Width 75.8 mm (2.98 in) 75.6 mm (2.98 in)
Thickness 7.3 mm (0.29 in) 8.9 mm (0.35 in)
Weight 190 g (6.7 oz) 227 g (8.01 oz)
Water resistance IP68 IP68
Cooling system Vapor chamber n/a
Back panel Glass Glass
Frame Metal Metal
Colors - Black
- Silver
- Gray
- Blue
- Green
- Pink		 - Black
- Silver
- Gray
- Blue
Fingerprint sensor Yes In-Display Yes In-Display
Screen-to-body ratio
Samsung Galaxy S25 Plus
91.7 %
Samsung Galaxy S21 Ultra
89.5 %

Performance

Testing Samsung Galaxy S25 Plus and Samsung Galaxy S21 Ultra In benchmarks
Processor
Chipset Qualcomm Snapdragon 8 Elite Samsung Exynos 2100
Max Frequency 4470 MHz 2900 MHz
CPU Cores 8 (2 + 6) 8 (1 + 3 + 4)
Architecture - 6/3.53 (Oryon (Phoenix M))
- 2/4.32 (Oryon (Phoenix L))		 - 4/2.2 (Cortex-A55)
- 3/2.81 (Cortex-A78)
- 1/2.91 (Cortex-X1)
Process TSMC Samsung
Transistor Size 3 nm 5 nm
Neural Processor Hexagon Yes
Graphics Adreno 830 Mali-G78 MP14
GPU Cores 1536 896
GPU Frequency 1100 MHz 854 MHz
FLOPS 3379.2 GFLOPS 1530.4 GFLOPS
GeekBench v6
Geekbench 6 (Single-Core)
Samsung Galaxy S25 Plus
3087
Samsung Galaxy S21 Ultra
1449
Geekbench 6 (Multi-Core)
Samsung Galaxy S25 Plus
9762
Samsung Galaxy S21 Ultra
3892
Geekbench 6 (Single-Core)30871449
Geekbench 6 (Multi-Core)97623892
Geekbench Compute (GPU)25122n/a
Sources: Geekbench v6 [Samsung Galaxy S25 Plus]
AnTuTu 10
AnTuTu 10
Samsung Galaxy S25 Plus
2136093
Samsung Galaxy S21 Ultra
843008
CPU466147232358
GPU1014939256356
Memory326456163007
UX328551191217
NanoReview Score2136093843008
3DMark Wild Life
3DMark Wild Life
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
5221
Max Surface Temp.n/a40.8 °C
Stabilityn/a69 %
Graphics Testn/a31 fps
Graphics Scoren/a5221
Sources: 3DMark [Samsung Galaxy S21 Ultra]

Memory

RAM
RAM Size 12 GB - 12 GB
- 16 GB
Memory Type LPDDR5X LPDDR5
Memory Frequency 5333 MHz 2750 MHz
Channels 2 2
Storage
Storage Capacity- 256 GB
- 512 GB		- 128 GB
- 256 GB
- 512 GB
Storage TypeUFS 4.0UFS 3.1
Memory CardNoNo

Software

OS Android 15 Android 11 (Upgradeable to Android 14)
OS Size 29.1 GB 26.4 GB
UI Skin One UI 7.0 One UI 6

Battery

Volume 4900 mAh 5000 mAh
Max Charging Power 45 W 25 W
Battery Type Li-ion Li-ion
Removable No No
Wireless Charging Yes (15 W) Yes (15 W)
Reverse Charging Yes (Wireless) Yes (Wireless)
Fast Charging Yes (75% in 30 min) Yes (54% in 30 min)
Full Charge Time 0:59 h 1:11 h
Battery Life Test
Battery Life
Samsung Galaxy S25 Plus
28:09
Samsung Galaxy S21 Ultra
22:05
Web Browsing10:20 h07:58 h
Video Playback18:29 h13:59 h
Games06:19 h05:14 h
Standby Mode137 h111 h

Main camera

Matrix 50 MP 108 MP
Photo resolution 8160x6120 pixels 12000x9000 pixels
Zoom Optical, 3x Optical, 10x
Flash LED Dual LED
Stabilization Optical Optical
8K Recording Yes (Up to 30 fps) Up to 24FPS
4K Recording Yes (Up to 60 fps) Yes (Up to 60 fps)
1080p Recording Yes (Up to 60 fps) Yes (Up to 60 fps)
Slow Motion 240 fps (1080p) 960 fps (720p)
Wide-angle lens 120 ° 120 °
Lenses count Standard: 50 MP
Telephoto: 10 MP
Ultra-wide: 12 MP		 Standard: 108 MP
Telephoto: 10 MP
Telephoto: 10 MP
Ultra-wide: 12 MP
Features - Bokeh effect
- Pro mode
- RAW support		 - Bokeh effect
- Pro mode
- RAW support
Main lens
Matrix50 MP108 MP
Aperturef/1.8f/1.8
Focal length24 mm26 mm
SensorSamsung ISOCELL S5KGN3Samsung S5KHM3
Sensor size1/1.561/1.33
Pixel size1 μm0.8 μm
AutofocusPhase autofocus (Dual Pixel)Laser autofocus
StabilizationOpticalOptical
Telephoto
Matrix10 MP10 MP
Aperturef/2.4f/4.9
Focal length67 mm240 mm
SensorSamsung ISOCELL S5K3K1Samsung S5K3J1
Sensor size1/3.941/2.65
Pixel size1 μm1.22 μm
StabilizationOpticalOptical
Ultra-wide lens
Matrix12 MP12 MP
Aperturef/2.2f/2.2
Focal length13 mm13 mm
SensorSony IMX564Sony IMX563
Sensor size1/2.551/2.55
Pixel size1.4 μm1.4 μm
StabilizationDigitalDigital
Main camera DxOMark results
Photo quality
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
121
Video quality
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
100
Overall camera score
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
115
Bokehn/a70
Previewn/a67
Zoomn/a106
Sources: DxOMark [Samsung Galaxy S21 Ultra]

Front camera

Matrix 12 MP 40 MP
Photo resolution 4000x3000 pixels 7864x5200 pixels
Aperture f/2.2 f/2.2
Focal length 26 mm 26 mm
Sensor Samsung S5K3LU Samsung S5KGH1
Sensor size 1/3.2 1/2.65
Pixel size 1.12 μm 0.7 μm
Autofocus Phase autofocus Phase autofocus
Stabilization Digital Digital
Video resolution 2160p (4K) at 60 fps 2160p (4K) at 60 fps
TOF 3D sensor No No
Selfie camera DxOMark results
Photo quality
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
133
Video quality
Samsung Galaxy S25 Plus
n/a
Samsung Galaxy S21 Ultra
140

Connectivity

Wi-Fi version Wi-Fi 7 (802.11 a/b/g/n/ac/ax/be) Wi-Fi 6E (802.11 a/b/g/n/ac/ax)
Wi-Fi features - Dual Band
- Wi-Fi MiMO
- Wi-Fi Direct
- Wi-Fi Hotspot
- Wi-Fi Display		 - Dual Band
- Wi-Fi MiMO
- Wi-Fi Direct
- Wi-Fi Hotspot
- Wi-Fi Display
Bluetooth version 5.4 5.2
Bluetooth features LE LE, A2DP
USB type USB Type-C USB Type-C
USB version 3.2 3.2
USB features - Charging
- USB Storage Mode
- OTG		 - Charging
- USB Storage Mode
- USB-Host mode
- OTG
DisplayPort Yes DP 1.2 n/a
GPS - GPS
- GLONASS
- Beidou
- Galileo
- QZSS		 - GPS
- GLONASS
- Beidou
- Galileo
NFC* Yes Yes
Infrared Port No No
Connectivity
SIM Count*12
SIM TypeNanoNano
SIM ModeDual SIM StandbyDual SIM Standby
eSIM Support *YesYes
Hybrid SlotNoNo
2G BandsGSM850,GSM900,DCS1800,PCS1900GSM 850, 900, 1800, 1900 MHz
3G BandsUMTS B1(2100),B2(1900),B4(AWS),B5(850),B8(900)WCDMA Band 1, 2, 4, 5, 8
LTE Bands*LTE (B1/B2/B3/B4/B5/B7/B8/B12/B13/B14/B18/B19/B20/B25/B26/B28/B29/B30/B66/B71)LTE (B1/B2/B3/B4/B5/B7/B8/B12/B13/B17/B18/B19/B20/B25/B26/B28/B32/B38/B39/B40/B41/B66)
LTE categoryn/a24
5G SupportYesYes

Sound

Speakers Stereo Stereo
3.5 mm Jack No No
FM Radio No No
Dolby Atmos Yes Yes
Speaker Test
Max Volume
Samsung Galaxy S25 Plus
90.9 dB
Samsung Galaxy S21 Ultra
88 dB

Other

Class Flagship Flagship
Announced January, 2025 yr January, 2021 yr
Release Date February, 2025 yr February, 2021 yr
Launch Price ($) 999 1200
Sensors - Hall Sensor
- Barometer
- Proximity Sensor
- Gyroscope
- Accelerometer
- Ambient Light Sensor
- Compass
- Fingerprint sensor		 - Hall Sensor
- Barometer
- Proximity Sensor
- Gyroscope
- Accelerometer
- Ambient Light Sensor
- Compass
- Fingerprint sensor
Charger Included No n/a

Note

Samsung Galaxy S25 Plus:

You can connect up to 2 eSIMs. The international model has 2 physical SIM slots, while the U.S. model has only one.

* Attention! Config, frequencies, NFC, and other specs may vary by region.

Results

After analyzing the data, we consider Samsung Galaxy S25 Plus the clear winner in this comparison.

Survey

Which smartphone would you pick?
1 (100%)
0 (0%)
Total Votes: 1

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