Table of Contents
TCL 55S421 Overview
The Class-4 Series TCL 55S421 is a smart 55 inch 4K UHD Roku TV with WiFi.

The Roku TCL TV provides access to over 500k content via its simple-to-use interface. The TV offers Dual band Wi-Fi, ethernet, and USB 2.0 connectivity options while lacking Bluetooth.
HDR10, TCL’s proprietary 4K Creative Pro technology, voice control through Siri, Google, and Alexa give 55S421 an edge over its competitors in the same segment. Read TCL 65S421 review.




Inclusions
- Quick Start Guide
- Roku TV RC280 remote control
- Two “AAA” remote batteries
Pros
- 4K UHD (3840 x 2160)
- Dual band WiFi and Ethernet
- 4K Creative Pro upscaling
- Easy navigation with 20 buttons RC282 remote
Cons
- No HDR10+
- No Bluetooth
- No Dolby Vision
Specifications
Brand | TCL |
Country | USA |
Series 2 | 4 |
Model | 55S421 |
Release Year | 2018 |
Size | 55 inch |
Smart TV | ✔ |
DISPLAY | |
Actual Size (Diagonal) | 54.6 inch |
Resolution | 4K UHD (3840 x 2160) |
Refresh Rate | 50 Hz/60 Hz |
Backlight Type | LED |
Color | 30 bits |
Color Depth | 1.07 billion |
Display Type | LCD |
Display Area | 91.16% |
LED Type | Direct LED |
Panel Bit Depth | 8 bits + FRC |
Frame Rate Control (FRC) | ✔ |
Panel Type | VA |
Screen Design | Flat |
Viewing Angle | 178 ° |
Aspect Ratio | 16:9 |
VIDEO | |
Frame Interpolation Frequency | 120Hz |
Upscaling | 4K Creative Pro |
Frame Interploation Technique | Clear Motion |
3D Capability | ✖ |
HDR10+ | ✖ |
Dolby Vision | ✖ |
Advanced HDR by Technicolor® | ✖ |
IMAX Enhanced | ✖ |
AMD Freesync™ | ✖ |
NVidia G-Sync | ✖ |
4K HFR | ✖ |
2K HFR | ✖ |
VRR | ✖ |
HGIG Compatibility | ✖ |
Black Frame Insertion | ✖ |
Filmmaker Mode | ✖ |
Auto Low Latency Mode | ✖ |
HDR10 | ✔ |
AUDIO | |
Speaker Power Rating | 8W + 8W |
Dolby Digital Plus | ✔ |
WiSA Ready | ✖ |
CONNECTIVITY | |
Ethernet Input | ✔ |
Wi-Fi | ✔ |
Wi-Fi Frequency | 2.4 GHz, 5 GHz |
Wi-Fi Protocol | 802.11ac 2×2 Dual Band (support 2.4GHz & 5GHz) |
Bluetooth | ✖ |
Chromecast | ✖ |
Google Home | ✖ |
Virtual Assistant | ✖ |
Works with Alexa | ✖ |
3.5mm headphone Audio Output | ✔ |
Component Inputs | ✖ |
Composite Inputs | ✔ |
HDCP Version | 2.2 |
HDMI Audio Return Channel (ARC) | ✔ |
HDMI Inputs | Three |
HDMI Version | Two |
HDMI-CEC | ✔ |
IF (Satellite) Inputs | ✖ |
Optical Audio Output | ✔ |
RCA Audio Outputs | ✖ |
RF (Terrestrial / Cable ) Inputs | One |
RS-232C Remote | ✖ |
USB 3.0 Ports | ✖ |
USB Inputs | One |
OTHER | |
Advanced PQ Setting with Mobile App | ✔ |
Closed Captions | ✔ |
CPU Cores | 2 |
GPU Cores | 2 |
Mobile App | ✔ |
On-Screen Display Languages | English, Spanish, French |
Operating System | Roku |
Parental Control (V-Chip) | ✔ |
Teletext | ✖ |
VIDEO FORMATS | |
3GPP | ✖ |
Accessible Menu System (CVAA) | ✔ |
ASF | ✖ |
AV1 | ✖ |
AVCHD | ✖ |
AVI | ✔ |
DivX | ✔ |
Flash Video | ✖ |
GIFV | ✖ |
H.263 | ✔ |
H.264 | ✔ |
H.265 | ✖ |
M2TS | ✖ |
MKV | ✔ |
MOV | ✔ |
MP4 | ✔ |
MPEG-2 | ✔ |
MPEG-4 | ✔ |
OCG | ✖ |
QuickTime | ✖ |
RealVideo | ✖ |
RM | ✖ |
TS | ✔ |
VC-1 | ✖ |
VOB | ✖ |
VP7 | ✖ |
VP8 | ✖ |
VP9 | ✖ |
VRO | ✖ |
WEBM | ✖ |
WebM | ✖ |
WMV | ✔ |
Xvid | ✖ |
AUDIO FORMATS | |
3GP | ✖ |
AA | ✖ |
AAC | ✔ |
AAX | ✖ |
AC4 | ✖ |
AIFF | ✖ |
ALAC | ✖ |
APE | ✖ |
aptX | ✖ |
AU | ✖ |
CDA | ✖ |
DSS | ✖ |
DVF | ✖ |
eAAC+ | ✖ |
EAC3 | ✖ |
FLAC | ✔ |
GSM | ✖ |
HE-AAC | ✖ |
IVS | ✖ |
LPCM | ✖ |
M4A | ✖ |
MIDI | ✖ |
MP2 | ✖ |
MP3 | ✔ |
OGG | ✖ |
OPUS | ✖ |
ORG | ✖ |
RAW | ✖ |
RealAudio | ✖ |
SLN | ✖ |
TTA | ✖ |
VOC | ✖ |
VOX | ✖ |
WAV | ✔ |
WMA | ✔ |
IMAGE FORMATS | |
BAT | ✖ |
BMP | ✔ |
CGM | ✖ |
EPS | ✖ |
Exif | ✖ |
GIF | ✔ |
GIF | ✖ |
HEIF | ✖ |
JPEG | ✔ |
JPS | ✖ |
MPO | ✖ |
PNG | ✔ |
PPM | ✖ |
RAW | ✖ |
SVG | ✖ |
TIFF | ✖ |
WebP | ✖ |
TUNER | |
Analog Tuner | NTSC |
Color system | PAL / SECAM / NTSC |
Digital Cable TV System | Clear QAM |
Digital Terrestrial TV System | ATSC |
Digital Tuner | ✔ 1 |
NEXTGEN TV (ATSC 3.0) | ✖ |
SAT Tuner | ✖ |
GENERAL | |
Power Supply | AC 120 V, 60 Hz |
Power Consumption (In Standby) | 0.5W |
Dimension Without Stand(W x H x D) | 49.09 x 28.50 x 3 inch (124.71 x 72.39 x 7.62 cm) |
Dimension With Stand (W x H x D) | 49.09 x 30.80 x 8.70 inch (124.71 x 78.23 x 22.1 cm) |
Stand Size | 42.3 inch (107.44 cm) |
Dimension of Package (W x H x D) | 55.1 x 34 x 6.6 inch (139.95 x 86.36 x 16.76 cm) |
VESA Wall Mount | ✔ |
VESA Hole Pitch (W x H) | 200 mm x 200 mm (7.87 x 7.87 inch) |
Wall mount screw | M6 x 12 |
Weight With Stand | 29.98 lbs (13.60 kg) |
Weight Without Stand | 29.54 lbs (13.40 kg) |
Weight of Package | 39.20 lbs (17.78 kg) |
Operating Temperature | 5 °C – 35 °C |
Operating Humidity | 20% – 80% |
WARRANTY | |
Warranty | 1 year limited warranty |
Final Verdict
We performed the TCL 55S421 review by testing and analyzing each aspect carefully.
Also, read TCL 55S423 review.
55S421 4K Roku TV is a nice addition by TCL in the 55 inch TV range. The TV boasts various features including HDR10, 4K Creative Pro Upscaling, Wi-Fi but lacks Bluetooth.
Frequently Asked Questions
Does the TCL 55S421 have Bluetooth?
TCL 55S421 Roku TV does not have Bluetooth.
Where to find the TCL 55S421 user manual?
You can download the TCL 55S421 Roku TV manual here.
What is the difference between TCL 55S421 and 55S425?
The price for TCL 55S421 is slightly lower than 55S425. 55S421 comes with Roku TV RC282 while 55S425 comes with Roku TV RC280.
When was 55S421 introduced?
It was introduced in the year 2018.