Convert a PDF to grayscale
Prepare a document for economical black-and-white printing.
Important limitation: this tool only converts images embedded in JPEG format to grayscale. Text and vector drawings remain unchanged. A scanned PDF (full-page photo/JPEG) will come out gray as expected; a text PDF or one with colored vector graphics will barely change visually.
How it works
The tool goes through each page of the PDF, locates images embedded and encoded as JPEG (the most common format for scans and photos in a PDF), decodes them, converts them to grayscale, then re-encodes them and reinserts them in place of the original color images. This lets you visually reduce the color saturation of a document before black-and-white printing, without having to open dedicated software.
Why does my text stay colored after the conversion?
Because that text isn't an image: it's vector text drawn directly by the PDF with its own color instructions. This tool, deliberately simple, only touches embedded JPEG images. On most printers, colored text prints as a satisfactory gray gradient anyway in "black and white" mode.
What about PNG images or non-JPEG scans?
They are not modified by this version of the tool, which focuses on the JPEG format (DCTDecode), by far the most common for images embedded in PDFs from scanners or cameras. An image in another format will simply be left as-is in the final document.
As with all our PDF tools, this conversion is calculated 100% locally in your browser thanks to WebAssembly: your document never leaves your device.