Why Print in Black & White?
Colour ink is the most expensive consumable in any office. Many documents only carry colour in a logo, a header band or a single chart, yet printing them in colour mode draws from the colour cartridges on every page. Converting to true grayscale first forces the printer to use black ink alone, which can cut the cost of a long print run dramatically and gives a consistent, professional monochrome finish across mixed-source documents.
Switching a printer to 'grayscale' in its dialog does not change the file β and many drivers still sip colour ink for 'rich black'. Converting the PDF itself removes the colour data completely, so there is nothing left for the printer to interpret. It also makes the file smaller and easier to archive.
Done Privately, In Your Browser
Each page is rendered, every pixel is recomputed to its grey value using a perceptual luminance formula, and the pages are reassembled into a new PDF β all on your device. Nothing is uploaded, so even confidential documents stay private.