Whiteprint describes a document reproduction produced by using the diazo chemical process. It is also known as the blue-line process since the result is blue lines on a white background. It is a contact printing process that accurately reproduces a translucent original in size, but can reproduce only limited tonal range and no color.

The light sensitivity of the chemicals used was known in the 1890s and several related printing processes were patented at that time. Whiteprinting replaced