Screen Size Calculator

Screen size is measured diagonally from one corner to the opposite corner. A 27-inch monitor means the diagonal distance is 27 inches. This is an industry standard dating back to CRT television days.

However, diagonal measurement alone doesn't tell you the actual width and height, which depend entirely on the aspect ratio. Two 27-inch monitors can have very different dimensions if one is 16:9 and the other is 21:9 ultrawide.

PPI (Pixels Per Inch) indicates how many pixels fit in one inch of screen space. Higher PPI means sharper images and text because more pixels are packed into the same physical area.

Practical examples:

• Desktop monitors (100-150 PPI): Comfortable for viewing at arm's length (2-3 feet)
• Laptops (150-220 PPI): Sharper for closer viewing (1.5-2 feet)
• Smartphones (300+ PPI): Retina quality for 10-12 inch viewing distance

The optimal PPI depends on your viewing distance. Closer viewing requires higher PPI to maintain sharpness.

Resolution (e.g., 1920×1080) is the total pixel count. When you spread the same number of pixels across different screen sizes, the pixel density changes dramatically.

This is why a 32-inch 1080p monitor may look "pixelated" compared to a 24-inch 1080p display, even though they have the same resolution.

For typical desktop use at 2-3 feet viewing distance, 90-120 PPI is the standard comfort range. However, the "best" PPI depends on your specific use case:

Resolution detection: 100% Accurate - The calculator reads your display's actual pixel count directly from the browser.

Diagonal size estimation: Approximate - This is calculated based on common screen configurations and pixel density assumptions.

For the most precise calculations, manually enter your exact diagonal size from your monitor's specifications. You can usually find this:

• On the monitor's product box or manual
• In the manufacturer's specifications online
• On a label on the back of the monitor
• In your system's display settings (sometimes)

16:9 (Standard Widescreen) is the most common aspect ratio for monitors, TVs, and laptops. It's ideal for general use, gaming, and video content.

21:9 (Ultrawide) provides significantly more horizontal space, making it excellent for productivity with multiple windows or immersive gaming experiences.

Key insight: A 34-inch 21:9 ultrawide has roughly the same height as a 27-inch 16:9 monitor but is significantly wider, essentially giving you the workspace of two 24-inch monitors side-by-side.

Dot pitch is the distance between the centers of adjacent pixels, measured in millimeters. It's the inverse relationship with PPI:

• Lower dot pitch = Higher PPI = Sharper image
• Higher dot pitch = Lower PPI = Less sharp image

Practical examples:

• 0.16mm dot pitch (~160 PPI) - High-quality laptop display
• 0.23mm dot pitch (~110 PPI) - Standard desktop monitor
• 0.31mm dot pitch (~82 PPI) - Lower-end or large display

Dot pitch is particularly important for displays viewed at close range. For desktop monitors, aim for 0.20-0.30mm. For laptops and tablets, 0.15-0.20mm provides excellent clarity.

Choosing the right screen size involves balancing several factors:

Desk Space

Measure your available desk depth. As a rule of thumb:

• 24-27 inches: Requires 24-30 inches of desk depth
• 32 inches: Requires 30-36 inches of desk depth
• 34" ultrawide: Requires 30-36 inches of desk depth

Viewing Distance

Optimal viewing distance = Screen diagonal × 1.2 to 1.5

• 24" monitor: 29-36 inches away
• 27" monitor: 32-41 inches away
• 32" monitor: 38-48 inches away

Use Case

Not necessarily. Resolution must be matched with appropriate screen size to achieve optimal pixel density. Consider these scenarios:

Resolution sweet spots by size:

• 24 inches: 1080p (92 PPI) or 1440p (122 PPI)
• 27 inches: 1440p (109 PPI) or 4K (163 PPI)
• 32 inches: 1440p (92 PPI) or 4K (138 PPI)
• 34" ultrawide: 3440×1440 (110 PPI)

Also consider:

• GPU requirements: 4K gaming needs significantly more power than 1440p
• Scaling issues: Very high PPI may require UI scaling, which can cause blurriness in some applications
• Content availability: Not all content benefits from 4K resolution

While often used interchangeably, there's a technical difference:

For consumer purposes: When you see "4K" on a monitor or TV, it almost always means 4K UHD (3840 × 2160). This is exactly 4× the pixels of 1080p Full HD.

Pixel count comparison:

• Full HD (1080p): 2.1 megapixels
• QHD (1440p): 3.7 megapixels
• 4K UHD: 8.3 megapixels (4× Full HD)
• 8K UHD: 33.2 megapixels (16× Full HD)