How to convert a PDF to grayscale
- Choose a Resolution. 150 DPI is a good start.
- Select Choose files or drop your PDF on the box. You can add several files.
- Wait while each page is drawn. Long files take a little longer.
- Select Download. The new file ends in
-grayscale.
If the file is locked, enter its password first.
What happens to your file
Each page is rendered the way a viewer would show it, including images, drawings, form values and annotations. The colors are then converted to shades of gray using the standard brightness formula, so red, green and blue keep their natural lightness. The gray pages are saved as images in a new PDF with the same page sizes.
This is the honest trade-off: text becomes non-selectable. The words are still there to read, but you cannot copy, search or highlight them, and links stop working. If you need those, keep your original and use the gray copy only for printing.
Good uses
- Save color ink or toner when you print slides, reports or forms.
- Prepare a black and white copy for a fax-style submission or an archive that asks for monochrome.
- Check how a design will look when printed without color.
- Make a scan look uniform when the paper was slightly yellow in some places.
Tips
- Printing a colorful presentation? Gray at 150 DPI is usually enough and keeps the file small.
- If the result is bigger than the original, run it through Compress PDF with Strong mode.
- Want pictures instead of a PDF? PDF to JPG saves every page as an image.
- To keep selectable text and only fix forms, use Flatten PDF.
- Turn sideways pages the right way up first with Rotate PDF.
Everything is drawn on your device with pdf.js and pdf-lib. Your document is never uploaded.