Calculate tools

Calculate tools answer questions about an image without changing the file. The DPI calculator works out print size, pixel dimensions or DPI from the other two values, and the DPI converter reads and rewrites the DPI stored in a JPG or PNG's metadata for print jobs that check it.

The file size calculator estimates how big an image will be at a given width, height and format, so you can plan before you have a real file, or drop in an existing image to see its exact dimensions, bit depth and compression ratio.

These tools are read only unless you explicitly ask for a change, such as converting DPI, and like every tool on this site they run entirely in your browser.

Use the DPI converter and calculator together when a print job or a passport photo needs a specific DPI value, and the file size calculator when planning a scan resolution, an export setting, or an upload ahead of actually having the file, or checking an existing file's exact size and bit depth after the fact. Neither tool changes an image's appearance, only its metadata or the numbers it reports back to you, which is why both process instantly with no quality setting to weigh up.