Monitor size comparison

40" 16:9 vs 45" 21:9: Full Size Comparison

Compare exact dimensions, pixel density, content size, and desk fit for these two displays.

Display 140 in 16:9
Display 245 in 21:9
Align:
41.4"17.7"34.9"19.6"
40 in 16:9
45 in 21:9

Specifications

Metric40 in 16:945 in 21:9Diff
Width34.86"41.36"+18.6%
Height19.61"17.73"-9.6%
Area683.7 in²733.2 in²+7.2%
Diagonal40"45"+12.5%
Pixel Density55 ppi123 ppi+124.2%
16:9 content40"36.16"-9.6%
4:3 content32.68"29.54"-9.6%
2.35:1 content37.89"44.95"+18.6%

The 40" 16:9 is 34.86" (88.6 cm) wide and 19.61" (49.8 cm) tall, while the 45" 21:9 is 41.36" (105.1 cm) wide and 17.73" (45 cm) tall. That makes the 45" 21:9 the larger screen by 7.2% of usable area.

The 40" 16:9 measures 34.86" (88.6 cm) wide by 19.61" (49.8 cm) tall, with a total screen area of 683.7 square inches. The 45" 21:9 measures 41.36" (105.1 cm) wide by 17.73" (45 cm) tall, covering 733.2 square inches.

In direct comparison: the 45" 21:9 is 18.6% wider, the 40" 16:9 is 9.6% taller, and 45" 21:9 offers 7.2% more screen area. The width delta is the main desk-fit number, while the height delta shows how much vertical space changes for documents, timelines, and video.

At 1920x1080, the 40" 16:9 achieves 55 PPI. The 45" 21:9 at 5120x2160 reaches 123 PPI. The 45" 21:9 has 124.2% higher pixel density, resulting in sharper text and images.

For 16:9 content (most videos and games), the 40" 16:9 provides an effective diagonal of 40", while the 45" 21:9 provides 36.2". This is crucial when comparing ultrawides to standard displays.

Frequently Asked Questions

What are the exact dimensions of a 40" 16:9 monitor?
A 40" 16:9 monitor measures 34.86" (88.6 cm) wide by 19.61" (49.8 cm) tall, with a screen area of 683.7 square inches.
What are the exact dimensions of a 45" 21:9 monitor?
A 45" 21:9 monitor measures 41.36" (105.1 cm) wide by 17.73" (45 cm) tall, with a screen area of 733.2 square inches.
Which is bigger: 40" 16:9 or 45" 21:9?
The 45" 21:9 is 7.2% larger in total screen area, though the 40" 16:9 may be taller depending on aspect ratio.
How much desk space do I need for a 45" 21:9?
A 45" 21:9 requires at least 41.36" of desk width. We recommend 47.36" to allow comfortable margins on each side.
Which has better pixel density: 40" 16:9 or 45" 21:9?
The 45" 21:9 at 5120x2160 has 123 PPI, which is 124.2% higher than the 40" 16:9's 55 PPI.
How does 16:9 content look on these displays?
On the 40" 16:9, 16:9 content appears at an effective 40" diagonal. On the 45" 21:9, it appears at 36.2". Ultrawides display 16:9 content with black bars on the sides.

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