Screen resolution calculator
Enter a resolution in pixels to get its simplified aspect ratio, its total number of megapixels, and, if you enter the screen diagonal, its pixel density (PPI). No data leaves your browser.
| Aspect ratio | 16:9 (1.778) |
| Total pixels | 2 073 600 px |
| Megapixels | 2.07 MP |
| Density (PPI) | 91.8 pixels/inch |
How it works
Useful for choosing a monitor, setting up a video project with the right format, or checking whether an image matches a screen's expected ratio (16:9, 21:9, 4:3...), this tool calculates the greatest common divisor between the width and height to simplify the ratio, counts the total number of pixels, and, if you specify the physical diagonal of the screen, calculates the pixel density per inch (PPI) via the Pythagorean theorem.
What is PPI and why does it matter?
PPI (pixels per inch) measures how fine a screen's display is: the higher it is, the sharper details and text appear to the naked eye at normal reading distance. A "Retina" or "4K" screen on a small diagonal will have a very high PPI, while a large 4K TV will have a more modest PPI despite an identical resolution, because the same pixels are spread over a larger surface.
Why isn't the ratio always a "round" number like 16:9?
Some resolutions don't correspond to any standard ratio (for example a cropped screenshot or an image exported with arbitrary dimensions): the calculation then shows the exact simplified ratio, which may be a less familiar fraction like 37:20 rather than 16:9 or 4:3.
This calculation is purely arithmetic and runs entirely in your browser, with no network exchange.