DPI Calculator — Convert Between DPI, Pixels & Print Size

DPI stands for Dots Per Inch. It describes how many dots of ink (or pixels) fit in one inch of printed output. Higher DPI means sharper prints. For digital screens, PPI (Pixels Per Inch) is the technically correct term.

For viewing distances under 50 cm (books, prints), 300 DPI is ideal. For posters viewed from 1+ metres, 150 DPI is fine. For billboards, even 30-72 DPI works because they are viewed from far away.

In Photoshop, go to Image > Image Size. In Procreate, check Canvas > Canvas Information. On Windows, right-click the file > Properties > Details. Note that DPI metadata can be changed without altering pixels.

PPI (Pixels Per Inch) refers to screen display, DPI (Dots Per Inch) to print output. They are often used interchangeably in digital art. When preparing files, the important thing is the total pixel count and desired print size.

Yes — changing DPI without resampling only changes the metadata (intended print size). The pixel count stays the same. In Photoshop, uncheck "Resample" in Image Size to change DPI without altering pixels.

Uncompressed size = width × height × bytes per pixel. At 8-bit per channel, RGB uses 3 bytes per pixel and CMYK 4 bytes (about 33% larger). A 3000 × 4000 px RGB image is 3000 × 4000 × 3 = 36,000,000 bytes ≈ 34.3 MB. Saved JPEGs and PNGs compress this considerably; the figure here is the raw/TIFF-style ceiling, useful for planning storage and RAM.

Bleed is extra image beyond the trim line (3mm each edge is the UK/EU print standard) so colour runs to the very edge after the guillotine cut. Enter bleed in Advanced Options: in Pixels → Print mode the calculator shows both the full sheet and the finished trimmed size; in Print → Pixels mode it adds the bleed back on so your file has enough pixels to cover it.