Samsung Galaxy S21: Full Specs, Features, and Details

El Samsung Galaxy S21 aims to establish itself as one of Samsung's most prominent flagship smartphones, bringing together innovation y premium features in a single device aimed at both demanding and professional users. Since its launch, attention surrounding this model has continued to grow, largely due to the quality that the Korean brand has historically demonstrated in its Galaxy family. Therefore, in this extensive and detailed article, we will break down absolutely all the specifications, features, functions, differences and details of the Galaxy S21 family (including S21, S21+ and S21 Ultra) comparing the different models, their memories, cameras and new features, as well as useful information on accessories, system, connectivity and user experience.

Models and versions available in the Samsung Galaxy S21 series

The Samsung Galaxy S21 family is made up of three main variants: Galaxy S21 (standard model), Galaxy S21+ (larger and with a larger battery) and Galaxy s21 ultra (the most advanced version aimed at professionals and premium users). Each one adapts to different profiles, but they share a powerful technological foundation and an elegant design.

• Samsung Galaxy S21: the most compact and lightest, with a 6,2-inch screen.
• Samsung Galaxy S21 +: with an enlarged screen of 6,7 inches and a larger battery.
• Samsung Galaxy S21 Ultra: the jewel in the crown, with a 6,8-inch panel, quad camera, S Pen compatibility, and the most advanced hardware.

Each model is available in variants of internal storage y exclusive colors, which allows the experience to be personalized according to the needs of each user.

Full technical specifications of the Samsung Galaxy S21

The Samsung Galaxy S21 not only boasts design, but also integrates the latest in mobile technology. This is especially visible on its 2-inch Dynamic AMOLED 6,2X display, with a resolution Full HD + (2.400 x 1.080 pixels), dynamic refresh rate up to 120Hz and HDR10+ support, ensuring an immersive, fluid and sharp visual experience in any ambient lighting situation.

• Display: Dynamic AMOLED 2X, 6,2 inches, FHD+ (2400 x 1080), 120 Hz, HDR10+, Gorilla Glass Victus protection.
• Processor: Exynos 2100 (international versions) or Snapdragon 888 (in specific regions such as the US, China, and Korea).
• RAM and storage: 8GB LPDDR5 RAM; 3.1GB or 128GB UFS 256 internal storage. No microSD expansion option.
• Battery: 4.000 mAh. 25W wired fast charging, 15W wireless charging, and 4,5W reverse wireless charging.
• Rear cameras: Triple sensor: 12 MP f/1.8 main (wide, OIS), 12 MP f/2.2 ultra-wide (120º) and 64 MP f/2.0 telephoto (3x hybrid zoom, digital up to 30x, OIS).
• Frontal camera: 10 MP f/2.2, Dual Pixel AF, 4K recording.
• Operating system: Android 11 with Samsung's One UI 3.1 interface (upgradable).
• Connectivity: Dual 5G, WiFi 6E, Bluetooth 5.0, NFC, USB-C 3.2, ANT+.
• Resistance: IP68 (protection against dust and water).
• Biometrics: Ultrasonic on-screen fingerprint reader and facial recognition.
• Other functions: Samsung DeX wireless and wired, stereo surround sound with AKG (no 3.5mm jack), Dolby Atmos, Always On Display, Bixby.
• Dimensions and weight: 151,7 x 71,2 x 7,9mm, 171 grams.

The S21 is a true beast in power, autonomy and performance, guaranteeing outstanding performance in both daily Homeworks as in photography, games and professional use.

Technical comparison with Galaxy S21+, S21 Ultra and other alternatives

To make a wise choice, it is essential to know the differences between the models:

As you can see, the S21 Ultra outperforms in every way: higher resolution display and size, quad camera with 108 MP main sensor and real optical zoom, up to 16GB of RAM, and a massive battery. However, both the standard S21 and the S21+ offer an excellent balance of size, weight, battery life, and power.

Design, materials and ergonomics: attractive, durable and functional

El Galaxy S21 design It introduces significant changes compared to previous generations. The new rear camera module stands out, harmoniously integrated into the metal chassis with a "Contour Cut" finish that provides robustness and distinction. On the back, Samsung has opted for Glasstic reinforced polycarbonate, a type of material that combines the lightness and strength of plastic with the premium feel of glass, easily preventing fingerprints and scratches.

The ergonomics are outstanding thanks to its reduced thickness and rounded edges, allowing you to operate the device with one hand without losing a secure grip. It's very comfortable for everyday use, and its well-distributed weight doesn't cause fatigue when typing or gaming.

Buttons and connections: On the right side are the volume and power buttons, easily accessible even for smaller hands. At the bottom, we find the USB-C port and the dual SIM tray, although there is no microSD card slot.

IP68 resistance: The S21 is waterproof and dustproof, so you can rest assured that it will not accidentally fall into water or dusty environments.

Available colors: The Samsung Galaxy S21 comes in gray, white, Phantom Violet, and pink, with special editions and exclusive finishes depending on the model and country. The S21+ and S21 Ultra come in black, silver, blue, titanium, brown, and even pink in certain limited editions.

Dynamic AMOLED 2X display: premium visual experience

One of the highlights of the Galaxy S21 is its impressive Dynamic AMOLED 2X display. With a 6,2″ diagonal and extra-thin bezels, it offers a virtually all-screen display. Its FHD+ resolution provides a pixel density of 412ppi, which translates to incredibly sharp text and graphics.

• 120Hz adaptive refresh rate: Provides extreme smoothness when browsing, gaming, or scrolling through menus. The system automatically adjusts the frequency based on the content, balancing fluidity and battery savings.
• Vibrant colors and total contrast thanks to HDR10+ certification, which enhances details in both dark and bright scenes.
• eye protection: Comfort Shield mode reduces blue light and automatically adjusts color temperature to protect your eyes during long periods of use.
• High maximum brightness: makes it easy to use outdoors even under strong sunlight.
• Multimedia playback: Excellent for watching movies, series, and gaming, it supports the latest high-quality streaming standards. The hole for the front camera is minimal and barely interferes with the experience.

Power, processor and real performance

The Galaxy S21 equips the powerful Exynos 2100 processor 5nm (in Europe and international markets) or the Snapdragon 888 (in the US, China and Korea). This architecture guarantees smooth performance and efficient, advanced power management and excellent graphics performance in demanding games.

• Octa-core CPU (1x Cortex-X1 @ 2,9 GHz, 3x Cortex-A78 @ 2,8 GHz, 4x Cortex-A55 @ 2,2 GHz).
• GPU Mali-G78 MP14 for games and advanced graphics applications.
• 5GB LPDDR8 RAM: Effortless multitasking with instantly open applications and intelligent memory management.
• 3.1 or 128GB UFS 256 Storage: Ultra-fast read and write speeds, although without a microSD slot.

Day-to-day performance: all tasks, from the professional photography until GamingFrom video editing to advanced office work and productivity, they run flawlessly. The device rarely heats up during normal use, and only during extended gaming sessions is a slight increase in temperature noticeable, which is well managed by its heat dissipation system.

In benchmarks like Geekbench 5, the S21 scores similar to the best smartphones on the market, placing it at the top of the high-end range.

Operating system and software: One UI, customization and features

The Galaxy S21 arrives with Android 11 and the custom interface One UI 3.1 (currently upgradeable to higher versions). One UI is recognized for its balance of advanced features, fluidity, and customization, optimizing the experience on Samsung phones, tablets, and wearables.

• Guaranteed updates: Samsung ensures multiple generations of system updates and monthly security patches.
• Cross-platform sync: Native integration with Galaxy ecosystem services and devices, as well as Windows, Google, and other popular services.
• Samsung DeX Wireless and Wired: Turn your phone into a desktop PC using a monitor, keyboard, and mouse—ideal for productivity.
• Bixby and automated routines: powerful assistant with options to automate actions based on schedules, location, and habits.
• Always On Display, advanced call effects, video calling, and exclusive features like Edge Screen.
• Pre-installed apps: Facebook, Instagram, Microsoft, Google, and Samsung services, most can be uninstalled if not in use.

Battery consumption at rest is highly optimized, and the entire layer works with a outstanding fluency, even in heavy tasks.

Biometrics, security and advanced unlocking

The Galaxy S21 integrates a ultrasonic fingerprint reader Under-screen touch with the latest generation of smart face unlock. The ultrasonic sensor increases the speed and area of ​​recognition, bringing it very close to the speed of conventional capacitive sensors. In addition, face unlock, while less secure, is fast and functional in most lighting conditions.

• You can register up to four fingerprints and configure them quickly and easily.
• Face unlock with the front camera, although it is not as secure as the fingerprint reader.
• Samsung Knox: advanced protection system for data, applications and services.

S Pen: Exclusive compatibility and accessories on the S21 Ultra

Version Samsung Galaxy S21 Ultra introduces support for the S Pen, the Note series' signature stylus. This transforms the productivity and creativity experience: you can take notes, draw, edit screenshots, and control your phone with professional precision. While the S21 Ultra doesn't have a built-in S Pen slot, it does offer dedicated cases and covers with a compartment for convenient carrying.

• S Pen Features: handwriting, text recognition, gesture remote control, advanced editing, quick access to note and drawing apps.
• Official accessories: cases with special accommodations and exclusive design accessories that protect the smartphone and the S Pen.

Photo and video capabilities: triple camera with professional technology

The Galaxy S21's photography system is one of its biggest draws, designed to deliver professional results in any circumstance. It features a triple rear camera covering a wide range of photographic uses and styles:

• 12 MP main sensor (f/1.8, OIS, Dual Pixel). Sharp, bright images even in low-light conditions.
• 12 MP ultra wide angle (f/2.2, 120º). Capture landscapes and scenes with great breadth and detail.
• 64MP Telephoto (f/2.0, OIS, 3x optical hybrid zoom, up to 30x digital zoom). It allows you to zoom in on distant details with virtually no loss of quality.
• 10 MP front camera with Dual Pixel autofocus and 4K video.

Advanced photography modes:

• Auto HDR to maximize dynamic range and balance between light and shadow.
• Night mode for incredible captures in low-light environments.
• Pro Mode to manually adjust parameters such as ISO, focus, shutter speed, white balance and exposure.
• Single catch that takes multiple photos and videos at once to effortlessly choose the best option.
• Picture with adjustable background blur, both on the rear and front cameras.
• Focus tracking of people and moving objects, while maintaining sharpness and framing.

Professional video: The S21 allows you to record video in up to 8K resolution (24fps), as well as 4K at up to 60fps and Full HD with slow motion (up to 960fps). It includes HDR10+ recording, optical stabilization, and professional modes for adjusting image and audio parameters (microphone selection, directionality, etc.).

The integration of artificial intelligence into the camera app is key to achieving impressive results without needing to be a photography expert. The transition between sensors is seamless, and the results maintain excellent consistency in colorimetry, dynamic range, and sharpness.

Audio and sound: high-fidelity stereo experience

Samsung equips the Galaxy S21 with a stereo audio signed by AKG, providing an immersive and balanced sound experience for videos, music, and games. The quality at low and medium volumes is outstanding, with good bass boost and clarity. At high volumes, there may be slight distortion, but overall, it's better than the average for high-end phones.

• Dolby Atmos support for surround sound on compatible content.
• Without 3.5 mm jack: It is possible to use headphones via USB-C or Bluetooth, with high-quality codecs (SBC, AAC, aptX, LDAC). Adapters must include an integrated DAC.
• Equalizer, Adapt Sound and UHQ optimizer to personalize the experience according to the user's tastes or age.
• Reverse Wireless Fast Charging: It allows you to share the battery with other devices (headphones, smart watches) by placing them on your phone.

Autonomy and charging: smart battery adapted to your rhythm

In the autonomy section, the Galaxy S21 has a 4.000 mAh battery This ensures a full day of intensive use. The intelligent management system adapts power consumption to each app and the user's habits, maximizing battery life at all times. Using the screen at 120Hz and playing continuously may shorten battery life, but the system compensates by adjusting the frequency when high performance isn't required.

• 25W fast charging via cable: Recharges the battery from 0 to 100% in approximately 1 hour and 30 minutes, with really fast partial charges.
• 15W fast wireless charging, perfect for compatible Samsung or third-party docks, and reverse wireless charging (4,5W) for charging accessories.
• Advanced energy saving: Multiple predefined and customizable saving modes (low consumption, maximum performance, etc.).

It highlights the optimization of standby power consumption, minimizing energy loss when the phone is not in use.

Full connectivity: 5G, WiFi 6E and NFC

The Galaxy S21 offers state-of-the-art connectivity To ensure speed, stability, and compatibility with any network and device, plus extras for payments, transportation, and home automation:

• Dual 5G: Maximum speed on mobile data, ideal for streaming, downloads, and high-quality video calls.
• Wi-Fi 6E: Take advantage of the new standard for ultra-fast and stable wireless connections, compatible with the latest generation of routers.
• Bluetooth 5.0: Greater range, speed, and energy efficiency when connecting accessories, headphones, watches, and other devices.
• NFC: mobile payments, access to public transport and synchronization with other devices.
• USB-C 3.2 for fast file transfer and peripheral connection.
• ANT +: Ready for sports and health gadgets such as heart rate monitors or smart bikes.
• Multi-band Global Positioning System: GPS, GLONASS, Galileo, BDS.

The S21 adds eSIM support (in select markets), increasing the flexibility to combine multiple lines into a single device and making it easier to switch carriers without a physical card.

Comparison with other models and previous generation

Compared to the Galaxy S20, the S21 offers significant improvements in power, efficiency, display, photography, and connectivity, as well as a more robust and attractive design. However, it's worth knowing the practical differences:

• The S21 gains in performance and battery life, but loses the microSD slot and reduces the maximum screen resolution in favor of an adaptive refresh rate.
• The camera module is similar in hardware, but improved software and AI allow for better results in night photography and portraits.
• Fast charging rivals the best in the industry, although Samsung no longer includes the fast charger in the box (recommending purchasing a compatible one to take advantage of the full power).
• The "Contour Cut" design for the camera module is one of the most distinctive and exclusive details of the S21.

Accessories and protection: official cases, covers, and extras

The S21 line has a wide variety of accessories and protections:

• Official cases and covers (Clear View, LED View, Silicone Cover, Protective Standing, etc.), including models with a compartment for the S Pen (on the Ultra) and with a stand for comfortable video viewing.
• Tempered glass and screen protectors adapted to the curvature of the device.
• Wireless charging bases fast and multi-device.
• Car mounts, DeX docks, and wireless keyboards.
• Galaxy Headphones and Wearables to squeeze the Samsung ecosystem.

You can check out the best cases and covers for the Galaxy S21 to protect your phone and increase its durability.

Alternative versions: Galaxy S21 FE (Fan Edition) and refurbished

Samsung has released versions such as the Galaxy S21 FE (Fan Edition), which trims and balances certain features to offer an experience close to the standard model but at a more affordable price. Additionally, refurbished options are available, with full warranties and lower prices, contributing to sustainability and the circular economy.

• Galaxy S21FE: slightly larger screen, similar processor and cameras tailored for a more affordable price range.
• Refurbished: Money-back guarantee and support, an excellent option for those seeking premium technology at a reduced cost and with a lower ecological impact.

Frequently asked questions and key tips before buying the Samsung Galaxy S21

Before choosing one of the Galaxy S21 series models, it's a good idea to be clear about some common questions:

• Can the memories be expanded? No, neither the S21, S21+, nor S21 Ultra support microSD. Choose the right storage from the start.
• Does it include a charger in the box? No, Samsung markets the fast charger separately to reduce waste and promote sustainability.
• What is the practical difference between FHD+ and QHD+? The S21 and S21+ feature FHD+; only the S21 Ultra features a QHD+ panel. In practice, the daily experience is similar except for the most resolution-demanding users.
• Do all models have 5G? Yes, the S21 family is fully compatible with 5G and WiFi 6E networks in supported markets.
• Which one should I choose if I'm interested in professional photography? The S21 Ultra is the most complete, but the S21 and S21+ cover all your advanced photography needs.

Opinion and user experience after months of use

For months, the Galaxy S21 has positioned itself as one of the best options in the high-end range. Users value above all the Screen quality, smooth performance, camera versatility, and operating system robustnessThe balance between compact size and power is its main advantage, making it the most manageable "top of the range" model currently available. Its strong points include:

• Spectacular, clear and fluid screen with minimal frames and outstanding brightness.
• Versatile cameras and advanced software which allows you to obtain professional photos in any circumstance.
• Very high overall performance, even in demanding games and tasks.
• Connectivity at the forefront and exclusive options like DeX, Bixby, and Samsung Pay.
• Iconic and ergonomic design, with premium IP68 protection.

Among the areas that could be improved are the lack of a microSD card and the lack of a fast charger in the box, decisions aligned with environmental sustainability and the general trend in high-end devices.

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Samsung Galaxy S21: Features, technical specifications, and everything you need to know about Samsung's flagship