Dots per inch

A close-up of the dots produced by an inkjet printer at draft quality. Actual size is approximately 1⁄4 by 1⁄4 inch (6 by 6 mm). Individual coloured droplets of ink are visible; this sample is about 150 DPI.

Dots per inch (DPI, or dpi^[1]) is a measure of spatial printing, video or image scanner dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch (2.54 cm). Similarly, dots per centimetre (d/cm or dpcm) refers to the number of individual dots that can be placed within a line of 1 centimetre (0.394 in).^[2]

^ The acronym appears in sources as either "DPI" or lowercase "dpi". See: "Print Resolution Understanding 4-bit depth – Xerox" Archived 2017-11-12 at the Wayback Machine (PDF). Xerox.com. September 2012.
^ CSS3 Media Queries Recommendation

[dpi-1] The acronym appears in sources as either "DPI" or lowercase "dpi". See: "Print Resolution Understanding 4-bit depth – Xerox" Archived 2017-11-12 at the Wayback Machine (PDF). Xerox.com. September 2012.

[2] CSS3 Media Queries Recommendation

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