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Samsung Galaxy S21

The Samsung Galaxy S21 went on sale on 29 January 2021, launched at £769 (Samsung Newsroom UK — Galaxy S21 5G and S21+ 5G). It has a 6.2-inch display, a weight of 169 g, the Exynos 2100, 5nm chip, a 12 MP main camera and 128 GB of storage to start. Samsung claims up to 20 hours of video playback. Security updates are committed until 21 February 2026. Every figure in the Samsung Galaxy S21 specifications below links the page it came from and the date it was read.

Press photograph of the Samsung Galaxy S21, from Samsung Newsroom.
Image: Samsung Newsroom
Released
2021-01-29endoflife.date, retrieved 2026-08-20
Price
£769Samsung Newsroom UK — Galaxy S21 5G and S21+ 5G, retrieved 2026-08-20

Peak brightness

1300nits

3rd party

Weight

169g

Official

Water/dust rating

IP68

Official

Specifications

Every figure carries its source, linked and dated.

Body

Dimensions
151.7 x 71.2 x 7.9 mmOfficial
Weight
169gOfficial
Build
Glass front (Gorilla Glass Victus), plastic back, aluminum frame3rd party
SIM
Nano-SIM + Nano-SIM + eSIM (max 2 at a time)3rd party
Water/dust rating
IP68Official
Unlock
Fingerprint SensorOfficial
151.7 mm71.2 mm7.9 mm
Drawn to scale from the published dimensions above. Outline only — the corner radius is our drawing convention, not a measurement.

Display

Display type
Dynamic AMOLED 2X Infinity-O, HDR10+ certified, Adaptive 120Hz, Eye Comfort ShieldOfficial
Display size
6.2inOfficial
Resolution
1080 x 2400Official
Pixel density
421ppiOfficial
Refresh rate
120HzOfficial
Peak brightness
1300nits3rd party
Screen protection
Corning Gorilla Glass Victus3rd party

Platform

Operating system
Android 11Official
Chipset
Exynos 2100, 5nmOfficial
CPU
Octa-core, 2.8GHz (maximum clock speed) + 2.4GHz + 1.8GHzOfficial
GPU
Mali-G78 MP143rd party

Memory

Storage (base)
128GBOfficial
Storage options
128GB/256GBOfficial
RAM
8GBOfficial
Card slot
No3rd party

Camera

Main camera
12MP Wide Dual Pixel AF OIS f/1.8; 64MP Telephoto hybrid optic 3x OIS f/2.0; 12MP Ultra-Wide f/2.2 FOV 120°; 10MP front Dual Pixel AF f/2.2Official
Main sensor resolution
12MPOfficial
Main aperture
f/1.8Official
Main sensor size
1/1.76"3rd party
Telephoto
64MP Telephoto, Hybrid Optic 3X, OIS, f/2.0Official
Ultrawide
12MP Ultra-Wide, f/2.2, FOV 120°Official
Front camera
10MP front Dual Pixel AF, f/2.2Official
Video capture
8K@24fps, 4K@30/60fps, HDR10+3rd party

Battery

Battery capacity
4000mAhOfficial
Claimed video playback
20hOfficial
Fast charging
25W3rd party
Wireless charging
15W3rd party

Connectivity

Wi-Fi
Wi-Fi 63rd party
Bluetooth
5.03rd party
USB
USB Type-C, DisplayPort over USB-C (4K UHD at 60 fps)Official
NFC
YesOfficial
Positioning
GPS, GLONASS, BDS, GALILEO3rd party

Benchmarks

Geekbench 6 (CPU, multi-core)
29733rd party

Geekbench Browser (Primate Labs), retrieved 2026-09-14

AnTuTu benchmark
7596683rd party

AnTuTu official ranking, retrieved 2026-09-14

DXOMARK camera score
1113rd party

DXOMARK, retrieved 2026-09-14

Misc

Colours
Phantom Violet, Phantom Grey, Phantom Pink, Phantom WhiteOfficial
SAR (EU, head)
0.46W/kg3rd party
8 attributes without a sourced figure yet

Typical brightness · HDR peak brightness · OS versions supported · Google Mobile Services · Battery per charge · Battery lifespan · 3DMark Wild Life Extreme · Repairability (EU class). A gap in our data, not a statement about the phone — rows appear as sources are cited.

What it actually costs

New against used, and what the same shop pays for the phone in your pocket.

New

recommended retail

£769

Samsung Newsroom UK — Galaxy S21 5G and S21+ 5G, retrieved 2026-08-20

Used, Grade A

cheapest of 8 colours

£185–£290

CeX, read 2026-10-05 · repriced 2026-08-14

Used, Grade B

cheapest of 9 colours

£170–£195

CeX, read 2026-10-05 · repriced 2026-08-14

Used, Grade C

cheapest of 9 colours

£135–£160

CeX, read 2026-10-05 · repriced 2026-08-14

Typical asking price (eBay UK)

median of 30 used listings

£142

eBay UK, read 2026-10-05

Trade in yours, Grade A

£116cash£125voucher

CeX, read 2026-10-05 · 8% more as store credit

Prices move; these were read on 2026-10-05. Used and trade-in figures are CeX's own, for an unlocked handset at this device's base storage. CeX prices each colour separately, so a grade shows as the range across them. The eBay figure is the middle of the used listings on sale that day — what sellers are asking, not what anyone paid. We hold no stock and take no commission.

Software support

Feature updates until
Security updates until

Basis: Maker commitment, via endoflife.date

endoflife.date records active (OS upgrade) support ending 2025-10-06 and security support ending 2026-02-21 for Galaxy S21 5G. Both windows had already closed by the 2026-08-20 access date. Samsung later listed the S21 series among devices eligible for four generations of OS upgrades and five years of security updates. These dates are Samsung's published window as recorded by endoflife.date, not a prediction of when updates actually stopped.

endoflife.date — Samsung mobile, retrieved 2026-09-06

The per-model page, with the maker’s commitment or Apple’s pattern: When does the Galaxy S21 stop getting updates?

Comparisons

The pairs a buyer of this phone would weigh, row by row with a verdict on each. Any other phone in the catalogue is a chooser away. Wondering whether to move at all? Should I upgrade my Galaxy S21?

Against its own line

Watches that work with this phone

17 of the 39 watches in the catalogue pair with the Galaxy S21, by the makers’ own compatibility statements. Full sheet on each watch’s page; all of them at Watches. Every watch sorted for this kind of phone, including the ones that do not pair: Which smartwatches work with Samsung phones?

Works in full 13

Every feature the maker lists works with the Galaxy S21.

WatchMaker’s compatibility statementSource
Garmin fēnix 9 43mm“Compatible with iPhone and Android”Garmin UK — fēnix 9 Pro 47 mm, retrieved 2026-09-13Official
Garmin fēnix 9 47mm“Compatible with iPhone and Android”Garmin UK — fēnix 9 Pro 47 mm, retrieved 2026-09-13Official
Garmin fēnix 9 51mm“Compatible with iPhone and Android”Garmin UK — fēnix 9 Pro 47 mm, retrieved 2026-09-13Official
Garmin fēnix 9 Pro 47mm“Compatible with iPhone and Android”Garmin UK — fēnix 9 Pro 47 mm, retrieved 2026-09-13Official
Galaxy Watch Ultra2 47mm“Android 13.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch Ultra2 and Watch9, retrieved 2026-09-13Official
Galaxy Watch9 40mm“Android 13.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch Ultra2 and Watch9, retrieved 2026-09-13Official
Galaxy Watch9 44mm“Android 13.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch Ultra2 and Watch9, retrieved 2026-09-13Official
Garmin Venu 4 41mm“Compatible with iPhone and Android”Garmin UK — Venu 4 41 mm, retrieved 2026-09-13Official
Garmin Venu 4 45mm“Compatible with iPhone and Android”Garmin UK — Venu 4 45 mm, retrieved 2026-09-13Official
Galaxy Watch Ultra 47mm“Android 11.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch8 series, retrieved 2026-09-13Official
Galaxy Watch8 40mm“Android 11.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch8 series, retrieved 2026-09-13Official
Galaxy Watch8 44mm“Android 11.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch8 series, retrieved 2026-09-13Official
Galaxy Watch8 Classic 46mm“Android 11.0 or higher and with more than 1.5GB of memory”Samsung Newsroom UK — Galaxy Watch8 series, retrieved 2026-09-13Official

Works, with the maker’s caveat 4

Pairs with the Galaxy S21; some features need the maker’s own phone. The maker’s words are quoted on each row.

WatchMaker’s compatibility statementSource
Google Pixel Watch 5 41mm“Works with most phones running on Android 12.0 or newer. Requires a Google Account and the Google Pixel Watch app.”Google Store UK — Pixel Watch 5 specs, retrieved 2026-09-13Official
Google Pixel Watch 5 45mm“Works with most phones running on Android 12.0 or newer. Requires a Google Account and the Google Pixel Watch app.”Google Store UK — Pixel Watch 5 specs, retrieved 2026-09-13Official
Google Pixel Watch 4 41mm“Works with most phones running on Android 11.0 or newer. Requires a Google Account and the Google Pixel Watch app.”Google Store UK — Pixel Watch 4 specs, retrieved 2026-09-13Official
Google Pixel Watch 4 45mm“Works with most phones running on Android 11.0 or newer. Requires a Google Account and the Google Pixel Watch app.”Google Store UK — Pixel Watch 4 specs, retrieved 2026-09-13Official