Photo enlargement

Online photo resolution increase calculator. The resolution of a large billboard on the roadside never requires such a high resolution as a gallery print viewed from a close distance. The following tool shows the minimum PPI and maximum print size, that can be used before the eye begins to distinguish individual pixels (without interpolation).

You can surely print a much larger size — just keep in mind that this sets a starting point from which you need to be cautious. Any print enlarged beyond this size will heavily depend on the quality of interpolation and sharpening.