Pixel density


DPI or dots per inch is a measure of the resolution of a printed document or digital scan. The higher the dot density, the higher the print or scan resolution. As a rule, DPI is a measure of the number of points that can be placed in a line inside an inch.

Higher DPI means sharper image. A higher resolution image provides more information to the printer and the printer device. You can get more  detail from images with higher DPI. 

A lower DPI creates an image with fewer dots when printing. No matter how powerful your printer is, a low-resolution image does not provide enough raw data to create high-quality images. The ink will spread across the page, making the edges look blurry.

Similarly, computer screen will measure the pixels per inch, or PPI, of a video display. The printer usually has to offer a higher DPI to match the color quality and resolution of the PPI video screen. This is due to the limited color palette in printers.

The terms dots per inch (DPI) and pixels per inch (PPI) are often used interchangeably to describe image resolution. However, the terms do not mean the same thing, and there are clear differences between the two:

DPI refers to the number of dots printed within one inch of the image printed by the printer.

PPI refers to the number of pixels that are within one inch of the image displayed on a computer screen.


PPI indicates the quality of the digital image displayed on the screen. But it also increases image quality. If there are too few pixels in the digital image, the image will not have as much detail and will be displayed in pixels. Multi-pixel digital images have better detail. The amount of PPI is determined by the image size.

By changing the aspect ratio of the DPI image, we can change the print size even if the actual number of pixels remains the same.

For most purposes, pixels and dots and ppi and dpi are interchangeable concepts. However, it is useful to separate them when calculating how many pixels will be needed to print an image of a certain size with a printer at a given dpi resolution.

A monitor or monitor with a large number of PPIs shows a higher level of detail. Similarly, a digital image with a large number of pixels contains more detailed visual information and can therefore be reproduced in larger formats without pixelation (a form of image distortion where individual pixels become visible to the naked eye).