Enter your screen resolution and diagonal size to calculate pixels per inch (PPI), total pixels, megapixels, and dot pitch. Use the presets for common display resolutions.
Pixel density determines how sharp text, images, and UI elements appear on a screen. Higher PPI means more pixels are packed into each inch, producing smoother edges and finer detail. This metric is essential when comparing monitors, phones, and tablets, or when designing assets that need to look crisp across different devices and viewing distances.
PPI (Pixels per Inch)—
Total Pixels—
Megapixels—
Dot Pitch—
About PPI
PPI (pixels per inch) measures pixel density — the number of pixels packed into one linear inch of a display. It is calculated by dividing the diagonal resolution (in pixels) by the diagonal screen size (in inches). A higher PPI results in sharper, more detailed visuals.
Below 100 PPI — individual pixels may be visible at normal viewing distances (typical for large TVs viewed up close)
100–150 PPI — standard for desktop monitors at arm's length
150–250 PPI — sharp for laptops and tablets
250+ PPI — "Retina" quality; individual pixels are imperceptible at normal use distance
Dot pitch is the inverse metric — the physical distance (in millimeters) between the centers of two adjacent pixels. Smaller dot pitch means higher density and sharper images.
FAQ
What is the difference between PPI and DPI?
PPI (pixels per inch) refers to the pixel density of a screen or digital image. DPI (dots per inch) refers to the dot density of a printed output. In everyday use the terms are often used interchangeably, but they technically apply to different media. A 300 DPI print and a 300 PPI display both have high density, but PPI describes screens while DPI describes printers and physical prints.
What is a Retina display?
Retina is Apple's marketing term for displays with a pixel density high enough that individual pixels cannot be distinguished by the human eye at a typical viewing distance. For phones held at about 10–12 inches, this threshold is roughly 300 PPI. For laptops at 18–20 inches, around 220 PPI is sufficient. For desktop monitors at arm's length (24–28 inches), roughly 110–140 PPI with 2x scaling achieves a similar effect.
What is a good PPI for a monitor?
It depends on the screen size and viewing distance. For a 24-inch desktop monitor, 92 PPI (1920x1080) is the baseline and 122 PPI (2560x1440) is noticeably sharper. For a 27-inch monitor, 109 PPI (2560x1440) is the sweet spot, and 163 PPI (3840x2160) is excellent. For laptops (13–15 inches), 150+ PPI is ideal. For phones (5–7 inches), 300+ PPI is standard in modern devices.
How is dot pitch calculated?
Dot pitch is calculated by dividing 25.4 (the number of millimeters in an inch) by the PPI value. For example, a display with 100 PPI has a dot pitch of 25.4 / 100 = 0.254 mm. A display with 300 PPI has a dot pitch of 25.4 / 300 = 0.085 mm. Smaller dot pitch means pixels are closer together and the image appears sharper.