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  1. Table of Contents
  2. Top
  3. Main Differences
  4. Design
    1. Style
    2. Stand
    3. Ergonomics
    4. Back
    5. Borders
    6. Thickness
    7. Build Quality
  5. Picture Quality
    1. Contrast
    2. Local Dimming
    3. SDR Peak Brightness
    4. HDR Peak Brightness
    5. Horizontal Viewing Angle
    6. Vertical Viewing Angle
    7. Gray Uniformity
    8. Black Uniformity
    9. Pre Calibration
    10. Post Calibration
    11. SDR Color Gamut
    12. SDR Color Volume
    13. HDR Color Gamut
    14. HDR Color Volume
    15. Image Retention
    16. Gradient
    17. Color Bleed
    18. Reflections
    19. Text Clarity
  6. Motion
    1. Response Time @ Max Refresh Rate
    2. Response Time @ 60Hz
    3. Image Flicker
    4. Black Frame Insertion (BFI)
    5. Refresh Rate
  7. Inputs
    1. Input Lag
    2. Resolution And Size
    3. Inputs
    4. Total Inputs
  8. Features
    1. Additional Features
    2. On-Screen Display (OSD)
    3. Controls
    4. In The Box
  9. Comments

Dell U3818DW vs Dell UltraSharp U4021QW

Side-by-Side Comparison

Products

Dell U3818DW
Dell UltraSharp U4021QW

Tested using Methodology v1.1

Updated Dec 16, 2022 03:14 PM

SEE PRICE
Amazon.com

Tested using Methodology v1.1

Updated May 03, 2024 05:02 PM

Amazon.com
Dell U3818DW Picture
Dell UltraSharp U4021QW Picture

Variants

  • U3818DW (38")
  • UltraSharp U4021QW (40")

Our Verdict

Dell U3818DW

Dell UltraSharp U4021QW

The Dell UltraSharp U4021QW is better overall than the Dell U3818DW. That said, they're quite similar in terms of features—neither has HDR support or VRR. The U4021QW is just bigger and has a higher resolution, and it outperforms the U3818DW in other areas. For instance, the U4021QW has a much faster response time, which is great if you want to do some light gaming on the side. It also has a wider color gamut, so it's a bit better for content creation.

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Main Differences for
Mixed Usage

Threshold 

0.10

Mixed Usage 

7.2
7.5
No major differences between these monitors for mixed usage. See full list of tests below.

Full Comparison

Design

Style  

Design Picture  

Dell U3818DW Design Picture
Dell UltraSharp U4021QW Design Picture

Size  

38"
40"

Curved  

Yes
Yes

Curve Radius  

2300R
2500R

Weight (without stand) 
 

19.6 lbs (8.9 kg)
20.9 lbs (9.5 kg)

Weight (with stand) 
 

25.4 lbs (11.5 kg)
30.4 lbs (13.8 kg)
Show Text 

Stand  

Stand Picture  

Dell U3818DW Stand Picture
Dell UltraSharp U4021QW Stand Picture

Width 
 

13.4" (34.0 cm)
15.2" (38.5 cm)

Depth 
 

8.9" (22.6 cm)
9.7" (24.7 cm)
Show Text 

Ergonomics 
 

6.4
6.4

Ergonomics Picture  

Dell U3818DW Ergonomics Picture
Dell UltraSharp U4021QW Ergonomics Picture

Height Adjustment 
 

4.7" (11.9 cm)
4.7" (12.0 cm)

Switch Portrait/Landscape  

No
No

Swivel Range  

-30° to 30°
-35° to 35°

Tilt Range  

-20° to 5°
-20° to 5°
Show Text 

Back  

Back Picture  

Dell U3818DW Back Picture
Dell UltraSharp U4021QW Back Picture

Wall Mount  

VESA 100x100
VESA 100x100
Show Text 

Borders  

Borders Picture  

Dell U3818DW Borders Picture
Dell UltraSharp U4021QW Borders Picture

Borders 
 

0.4" (1.0 cm)
0.4" (1.1 cm)
Show Text 

Thickness  

Thickness Picture  

Dell U3818DW Thickness Picture
Dell UltraSharp U4021QW Thickness Picture

Thickness (with stand) 
 

6.5" (16.5 cm)
8.3" (21.1 cm)

Thickness (without stand) 
 

3.8" (9.7 cm)
4.0" (10.1 cm)
Show Text 

Build Quality 
 

8.0
7.0

Build Quality Picture  

Dell U3818DW Build Quality Picture
Dell UltraSharp U4021QW Build Quality Picture
Show Text 
Picture Quality

Contrast 
 

6.2
5.9

Checkerboard Picture  

Dell U3818DW Checkerboard Picture
Dell UltraSharp U4021QW Checkerboard Picture

Native Contrast 
 

1,133 : 1
943 : 1

Contrast With Local Dimming 
 

N/A
N/A
Show Text 

Local Dimming 
 

0.0
0.0

Local Dimming Video  

Local Dimming 
 

No
No

Backlight 
 

Edge
Edge
Show Text 

SDR Peak Brightness 
 

7.3
7.1

SDR Real Scene 
 

278 cd/m²
256 cd/m²

SDR Peak 2% Window 
 

302 cd/m²
279 cd/m²

SDR Peak 10% Window 
 

302 cd/m²
279 cd/m²

SDR Peak 25% Window 
 

302 cd/m²
280 cd/m²

SDR Peak 50% Window 
 

302 cd/m²
280 cd/m²

SDR Peak 100% Window 
 

302 cd/m²
280 cd/m²

SDR Sustained 2% Window 
 

301 cd/m²
278 cd/m²

SDR Sustained 10% Window 
 

302 cd/m²
279 cd/m²

SDR Sustained 25% Window 
 

302 cd/m²
279 cd/m²

SDR Sustained 50% Window 
 

302 cd/m²
279 cd/m²

SDR Sustained 100% Window 
 

302 cd/m²
280 cd/m²

SDR ABL 
 

0.000
0.000
Show Text 

HDR Peak Brightness 
 

0.0
0.0

HDR Real Scene 
 

N/A
N/A

HDR Peak 2% Window 
 

N/A
N/A

HDR Peak 10% Window 
 

N/A
N/A

HDR Peak 25% Window 
 

N/A
N/A

HDR Peak 50% Window 
 

N/A
N/A

HDR Peak 100% Window 
 

N/A
N/A

HDR Sustained 2% Window 
 

N/A
N/A

HDR Sustained 10% Window 
 

N/A
N/A

HDR Sustained 25% Window 
 

N/A
N/A

HDR Sustained 50% Window 
 

N/A
N/A

HDR Sustained 100% Window 
 

N/A
N/A

HDR ABL 
 

N/A
N/A
Show Text 

Horizontal Viewing Angle 
 

8.1
8.0

Horizontal Viewing Angle Video  

Horizontal Chroma Graph  

Dell U3818DW Horizontal Chroma Graph
Dell UltraSharp U4021QW Horizontal Chroma Graph

Color Washout From Left 
 

47°
43°

Color Washout From Right 
 

47°
45°

Horizontal Hue Graph  

Dell U3818DW Horizontal Hue Graph
Dell UltraSharp U4021QW Horizontal Hue Graph

Color Shift From Left 
 

53°
49°

Color Shift From Right 
 

55°
51°

Horizontal Lightness Graph  

Dell U3818DW Horizontal Lightness Graph
Dell UltraSharp U4021QW Horizontal Lightness Graph

Brightness Loss From Left 
 

51°
49°

Brightness Loss From Right 
 

51°
51°

Black Level Raise From Left 
 

70°
70°

Black Level Raise From Right 
 

40°
70°

Gamma Shift From Left 
 

46°
40°

Gamma Shift From Right 
 

56°
41°
Show Text 

Vertical Viewing Angle 
 

7.4
7.1

Vertical Viewing Angle Video  

Vertical Chroma Graph  

Dell U3818DW Vertical Chroma Graph
Dell UltraSharp U4021QW Vertical Chroma Graph

Color Washout From Below 
 

34°
33°

Color Washout From Above 
 

35°
30°

Vertical Hue Graph  

Dell U3818DW Vertical Hue Graph
Dell UltraSharp U4021QW Vertical Hue Graph

Color Shift From Below 
 

40°
38°

Color Shift From Above 
 

43°
33°

Vertical Lightness Graph  

Dell U3818DW Vertical Lightness Graph
Dell UltraSharp U4021QW Vertical Lightness Graph

Brightness Loss From Below 
 

36°
36°

Brightness Loss From Above 
 

37°
32°

Black Level Raise From Below 
 

70°
70°

Black Level Raise From Above 
 

70°
70°

Gamma Shift From Below 
 

41°
43°

Gamma Shift From Above 
 

44°
36°
Show Text 

Gray Uniformity 
 

8.1
8.5

50% Uniformity Picture  

Dell U3818DW 50% Uniformity Picture
Dell UltraSharp U4021QW 50% Uniformity Picture

50% Std. Dev. 
 

3.831%
2.994%

50% DSE 
 

0.136%
0.122%

5% Uniformity Picture  

Dell U3818DW 5% Uniformity Picture
Dell UltraSharp U4021QW 5% Uniformity Picture

5% Std. Dev. 
 

0.474%
0.398%

5% DSE 
 

0.045%
0.032%
Show Text 

Black Uniformity 
 

5.8
6.8

Native Black Uniformity Picture  

Dell U3818DW Native Black Uniformity Picture
Dell UltraSharp U4021QW Native Black Uniformity Picture

Native Std. Dev. 
 

2.137%
1.434%

Black Uniformity Picture With Local Dimming  

Dell U3818DW Black Uniformity Picture With Local Dimming
Dell UltraSharp U4021QW Black Uniformity Picture With Local Dimming

Std. Dev. w/ L.D. 
 

N/A
N/A
Show Text 

Pre Calibration 
 

9.0
9.1

Pre Calibration Picture  

Dell U3818DW Pre Calibration Picture
Dell UltraSharp U4021QW Pre Calibration Picture

Pre Gamma Curve Picture  

Dell U3818DW Pre Gamma Curve Picture
Dell UltraSharp U4021QW Pre Gamma Curve Picture

Pre Color Picture  

Dell U3818DW Pre Color Picture
Dell UltraSharp U4021QW Pre Color Picture

Picture Mode 
 

Standard
Color Space (sRGB)

Luminance 
 

242 cd/m²
210 cd/m²

Luminance Settings 
 

75
75

Contrast Setting 
 

75
75

RGB Controls 
 

100-100-100
Default

Gamma Setting 
 

Default
No Gamma Setting

Color Temperature 
 

6,593 K
6,281 K

White Balance dE 
 

1.67
1.50

Color dE 
 

1.32
0.99

Gamma 
 

2.20
2.16
Show Text 

Post Calibration 
 

9.6
9.7

Post Calibration Picture  

Dell U3818DW Post Calibration Picture
Dell UltraSharp U4021QW Post Calibration Picture

Post Gamma Curve Picture  

Dell U3818DW Post Gamma Curve Picture
Dell UltraSharp U4021QW Post Gamma Curve Picture

Post Color Picture  

Dell U3818DW Post Color Picture
Dell UltraSharp U4021QW Post Color Picture

Picture Mode 
 

Custom Color
Custom Color

Luminance 
 

102 cd/m²
100 cd/m²

Luminance Settings 
 

23
28

Contrast Setting 
 

75
75

RGB Controls 
 

100-99-98
98-97-100

Gamma Setting 
 

Default
No Gamma Setting

Color Temperature 
 

6,420 K
6,456 K

White Balance dE 
 

0.67
0.65

Color dE 
 

0.54
0.31

Gamma 
 

2.17
2.18
Show Text 

SDR Color Gamut 
 

8.9
9.4

Color Gamut sRGB Picture  

Dell U3818DW Color Gamut sRGB Picture
Dell UltraSharp U4021QW Color Gamut sRGB Picture

sRGB xy 
 

99.0%
100.0%

Color Gamut ARGB Picture  

Dell U3818DW Color Gamut ARGB Picture
Dell UltraSharp U4021QW Color Gamut ARGB Picture

Adobe RGB xy 
 

77.6%
88.5%

sRGB Picture Mode 
 

Custom Color
Custom Color

Adobe RGB Picture Mode 
 

Custom Color
Custom Color
Show Text 

SDR Color Volume 
 

9.1
9.6

sRGB Color Volume ITP Picture  

Dell U3818DW sRGB Color Volume ITP Picture
Dell UltraSharp U4021QW sRGB Color Volume ITP Picture

sRGB In ICtCp 
 

97.8%
98.2%

Adobe RGB Color Volume ITP Picture  

Dell U3818DW Adobe RGB Color Volume ITP Picture
Dell UltraSharp U4021QW Adobe RGB Color Volume ITP Picture

Adobe RGB In ICtCp 
 

83.0%
93.2%

sRGB Picture Mode 
 

Custom Color
Custom Color

Adobe RGB Picture Mode 
 

Custom Color
Custom Color
Show Text 

HDR Color Gamut 
 

0.0
0.0

Wide Color Gamut 
 

No
N/A

Color Gamut DCI-P3 Picture  

Dell U3818DW Color Gamut DCI-P3 Picture
Dell UltraSharp U4021QW Color Gamut DCI-P3 Picture

DCI P3 xy 
 

N/A
N/A

Color Gamut Rec.2020 Picture  

Dell U3818DW Color Gamut Rec.2020 Picture
Dell UltraSharp U4021QW Color Gamut Rec.2020 Picture

Rec. 2020 xy 
 

N/A
N/A

DCI P3 Picture Mode 
 

No HDR
No HDR

Rec. 2020 Picture Mode 
 

No HDR
No HDR
Show Text 

HDR Color Volume 
 

0.0
0.0

P3 Color Volume ITP Picture  

Dell U3818DW P3 Color Volume ITP Picture
Dell UltraSharp U4021QW P3 Color Volume ITP Picture

DCI-P3 In ICtCp 
 

N/A
N/A

2020 Color Volume ITP Picture  

Dell U3818DW 2020 Color Volume ITP Picture
Dell UltraSharp U4021QW 2020 Color Volume ITP Picture

Rec. 2020 In ICtCp 
 

N/A
N/A

DCI P3 Picture Mode 
 

No HDR
No HDR

Rec. 2020 Picture Mode 
 

No HDR
No HDR
Show Text 

Image Retention 
 

10
10

Image Retention Picture  

Dell U3818DW Image Retention Picture
Dell UltraSharp U4021QW Image Retention Picture

IR After 0 Min Recovery 
 

0.00%
0.00%

IR After 2 Min Recovery 
 

0.00%
0.00%

IR After 4 Min Recovery 
 

0.00%
0.00%

IR After 6 Min Recovery 
 

0.00%
0.00%

IR After 8 Min Recovery 
 

0.00%
0.00%

IR After 10 Min Recovery 
 

0.00%
0.00%
Show Text 

Gradient 
 

9.4
9.8

Gradient Picture  

Dell U3818DW Gradient Picture
Dell UltraSharp U4021QW Gradient Picture

Color Depth 
 

10 Bit
10 Bit
Show Text 

Color Bleed 
 

10
10

Color Bleed Horizontal  

Dell U3818DW Color Bleed Horizontal
Dell UltraSharp U4021QW Color Bleed Horizontal

Pixel Row Error 
 

0.000%
0.001%

Color Bleed Vertical  

Dell U3818DW Color Bleed Vertical
Dell UltraSharp U4021QW Color Bleed Vertical

Pixel Column Error 
 

0.001%
0.001%
Show Text 

Reflections 
 

6.4
6.7

Average Room  

Dell U3818DW Average Room
Dell UltraSharp U4021QW Average Room

Average Room Off Picture  

Dell U3818DW Average Room Off Picture
Dell UltraSharp U4021QW Average Room Off Picture

Bright Room Off Picture  

Dell U3818DW Bright Room Off Picture
Dell UltraSharp U4021QW Bright Room Off Picture

Screen Finish 
 

Matte
Matte

Total Reflections 
 

7.5%
6.6%

Indirect Reflections 
 

4.3%
3.2%

Calculated Direct Reflections 
 

3.2%
3.4%
Show Text 

Text Clarity 
 

7.0
9.5

ClearType On  

Dell U3818DW ClearType On
Dell UltraSharp U4021QW ClearType On

Pixel Type 
 

IPS
IPS

ClearType Off  

Dell U3818DW ClearType Off
Dell UltraSharp U4021QW ClearType Off

Pixels  

Dell U3818DW Pixels
Dell UltraSharp U4021QW Pixels

Sub-Pixel Layout 
 

RGB
RGB
Show Text 
Motion

Response Time @ Max Refresh Rate 
 

4.9
7.2

Motion Blur Picture  

Dell U3818DW Motion Blur Picture
Dell UltraSharp U4021QW Motion Blur Picture

Response Time Table  

Dell U3818DW Response Time Table
Dell UltraSharp U4021QW Response Time Table

Best Overdrive Setting 
 

Normal
Normal

Rise / Fall Time 
 

6.6 ms
6.5 ms

Total Response Time 
 

26.0 ms
18.7 ms

Overshoot Error 
 

17.6%
7.5%

Dark Rise / Fall Time 
 

6.5 ms
6.6 ms

Dark Total Response Time 
 

25.3 ms
20.3 ms

Dark Overshoot Error 
 

18.7%
12.5%
Show Text 

Response Time @ 60Hz 
 

4.9
7.2

Motion Blur Picture  

Dell U3818DW Motion Blur Picture
Dell UltraSharp U4021QW Motion Blur Picture

Response Time Table  

Dell U3818DW Response Time Table
Dell UltraSharp U4021QW Response Time Table

Best Overdrive Setting 
 

Normal
Normal

Rise / Fall Time 
 

6.6 ms
6.5 ms

Total Response Time 
 

26 ms
18.7 ms

Overshoot Error 
 

17.6%
7.5%

Dark Rise / Fall Time 
 

6.5 ms
6.6 ms

Dark Total Response Time 
 

25.3 ms
20.3 ms

Dark Overshoot Error 
 

18.7%
12.5%
Show Text 

Image Flicker 
 

10
10

Backlight Picture  

Dell U3818DW Backlight Picture
Dell UltraSharp U4021QW Backlight Picture

Flicker-Free  

Yes
Yes

PWM Dimming Frequency 
 

0 Hz
0 Hz
Show Text 

Black Frame Insertion (BFI) 
 

0.0
0.0

Black Frame Insertion (BFI) 
 

No
No BFI

BFI Picture  

Dell U3818DW BFI Picture
Dell UltraSharp U4021QW BFI Picture

BFI Frequency Picture  

Dell U3818DW BFI Frequency Picture
Dell UltraSharp U4021QW BFI Frequency Picture

BFI Maximum Frequency 
 

N/A
N/A

BFI Minimum Frequency 
 

N/A
N/A
Show Text 

Refresh Rate 
 

5.9
5.9

Variable Refresh Rate 
 

No VRR
No VRR

Native 
 

60 Hz
60 Hz

Max Refresh Rate 
 

60 Hz
60 Hz

Variable Refresh Rate 
 

No
No

FreeSync 
 

No
No

G-SYNC 
 

No
No

VRR Maximum 
 

N/A
N/A

VRR Minimum 
 

No VRR
No VRR

VRR Supported Connectors  

No VRR
No VRR
Show Text 
Inputs

Input Lag 
 

8.9
9.0

Native Resolution 
 

9.2 ms
8.9 ms

Native Resolution @ 60Hz 
 

9.2 ms
8.9 ms

Variable Refresh Rate 
 

N/A
N/A

Variable Refresh Rate @ 60Hz 
 

N/A
N/A

10 Bit HDR 
 

N/A
N/A

Black Frame Insertion (BFI) 
 

N/A
N/A
Show Text 

Resolution And Size 
 

8.9
9.4

Native Resolution  

3840 x 1600
5120 x 2160

Aspect Ratio  

21:9
21:9

Megapixels  

6.1 MP
11.1 MP

Pixel Density 
 

111 PPI
137 PPI

Screen Diagonal  

37.5"
40.0"

Screen Area  

498 in²
581 in²
Show Text 

Inputs  

Inputs 1  

Dell U3818DW Inputs 1
Dell UltraSharp U4021QW Inputs 1

Inputs 2  

Dell U3818DW Inputs 2
Dell UltraSharp U4021QW Inputs 2

Total Inputs  

DisplayPort  

1 (DP 1.2)
1 (DP 1.4)

Mini DisplayPort  

No
No

HDMI  

2 (HDMI 2.0)
2 (HDMI 2.0)

DVI  

No
No

VGA  

No
No

DisplayPort Out  

No
No

USB  

4 (USB 3.0)
4 (USB 3.0)

USB C  

1 (USB, USB PD, DP Alt Mode)
2 (1x Thunderbolt 3, PD, DP Alt Mode, 1x USB 3.2 Gen 2)

Analog Audio Out 3.5mm  

1
1

Microphone In 3.5mm  

No
No

Digital Optical Audio Out  

No
No

Analog Audio Out RCA  

No
No

Power Supply  

Internal
Internal
Show Text 
Features

Additional Features 
 

RGB Illumination 
 

No
No

Speakers 
 

Yes
Yes

HDR10  

No
No

Multiple Input Display 
 

PIP + PBP
PIP + PBP
Show Text 

On-Screen Display (OSD)  

OSD Picture  

Dell U3818DW OSD Picture
Dell UltraSharp U4021QW OSD Picture

Controls  

Controls Picture  

Dell U3818DW Controls Picture
Dell UltraSharp U4021QW Controls Picture
Show Text 

In The Box  

In The Box Picture  

Dell U3818DW In The Box Picture
Dell UltraSharp U4021QW In The Box Picture
Show Text 

Check Price

40"
UltraSharp U4021QW
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40"
UltraSharp U4021QW
Searching
Finding store
40"
UltraSharp U4021QW
Searching
Finding store
40"
UltraSharp U4021QW
Searching
Finding store
40"
UltraSharp U4021QW
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Dell U3818DW

Dell UltraSharp U4021QW

Comments

  1. Comparison

Dell U3818DW vs Dell UltraSharp U4021QW: Main Discussion

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