The 40-inch ultrawide is 36.77" (93.4 cm) wide and 15.76" (40 cm) tall, while the 45-inch super ultrawide is 43.32" (110 cm) wide and 12.18" (30.9 cm) tall. That makes the 40-inch ultrawide the larger screen by 8.9% of usable area.
The 40-inch ultrawide measures 36.77" (93.4 cm) wide by 15.76" (40 cm) tall, with a total screen area of 579.3 square inches. The 45-inch super ultrawide measures 43.32" (110 cm) wide by 12.18" (30.9 cm) tall, covering 527.8 square inches.
The practical difference: the 45-inch super ultrawide is 17.8% wider, the 40-inch ultrawide is 22.7% taller, and 40-inch ultrawide offers 8.9% more screen area. Width affects how much desk space you need, while the height delta shows how much vertical space changes for documents, timelines, and video.
The practical choice depends on what feels limiting in your current setup. For coding, timelines, spreadsheets, and games, the wider option gives more room for side-by-side windows, while the taller option keeps more vertical content visible without pushing the edges of the screen as far away. If your desk is shallow, width and viewing distance matter as much as raw diagonal size.
40-inch 21:9 vs 45-inch 32:9 is mostly about side-by-side workspace. A 21:9 display behaves like one wide main workspace, while a 32:9 super ultrawide is closer to two monitors fused into one panel. The physical width number matters more than the diagonal when you are checking speakers, arms, laptop stands, or portrait side screens.
At 5120x2160, the 40-inch ultrawide achieves 139 PPI. The 45-inch super ultrawide at 5120x1440 reaches 118 PPI. The 40-inch ultrawide has 14.9% higher pixel density, resulting in sharper text and images.
For text-heavy work, PPI is the number that decides whether you are buying more room or just making everything bigger. A lower-PPI large screen can feel spacious for windows but softer for code and documents. A higher-PPI screen may need OS scaling, but it usually gives cleaner text and more flexible sizing.
For 16:9 content (most videos and games), the 40-inch ultrawide provides an effective diagonal of 32.1", while the 45-inch super ultrawide provides 24.9". Check this if you watch 16:9 video or play games that do not support ultrawide resolutions.
Frequently Asked Questions
- What are the exact dimensions of a 40-inch ultrawide?
- A 40-inch ultrawide measures 36.77" (93.4 cm) wide by 15.76" (40 cm) tall, with a screen area of 579.3 square inches.
- What are the exact dimensions of a 45-inch super ultrawide?
- A 45-inch super ultrawide measures 43.32" (110 cm) wide by 12.18" (30.9 cm) tall, with a screen area of 527.8 square inches.
- Which is bigger: 40-inch ultrawide or 45-inch super ultrawide?
- The 40-inch ultrawide is 8.9% larger in total screen area.
- How much desk space do I need for a 45-inch super ultrawide?
- A 45-inch super ultrawide requires at least 43.32" of desk width. We recommend 49.32" to allow comfortable margins on each side.
- How wide is 40-inch ultrawide compared with 45-inch super ultrawide?
- The 40-inch ultrawide is 36.77" wide. The 45-inch super ultrawide is 43.32" wide, so the width change is 6.55" before bezels, arms, or speaker space.
- Which has better pixel density: 40-inch ultrawide or 45-inch super ultrawide?
- The 40-inch ultrawide at 5120x2160 has 139 PPI, which is 14.9% higher than the 45-inch super ultrawide's 118 PPI.
- How does 16:9 content look on these displays?
- On the 40-inch ultrawide, 16:9 content appears at an effective 32.1" diagonal. On the 45-inch super ultrawide, it appears at 24.9". Ultrawides display 16:9 content with black bars on the sides.