Convert PDF to Black and White (Grayscale)
Turn a colour PDF into black and white, so every page is shades of grey on screen and on paper.
Select a PDF fileor drop it anywhere on this page, or paste
Opens in your browser. Nothing is uploaded.
Convert PDF to Black and White (Grayscale), free and private
Convert a PDF to black and white, so every page is in shades of grey (grayscale). The file itself holds no colour, not only the printout, which is what upload portals and print shops usually ask for.
Each page is drawn with pdf.js, turned grey on your device and saved into a new PDF with pdf-lib. The tool is free and your document is never uploaded.
How to convert a PDF to black and white
- 1
Add your PDF
Press Select PDF files or drop a PDF onto the page. The tool converts one file at a time.
- 2
Check the preview and pick a quality
Drag the divider on the preview to compare your page in colour and in grey, and flip through the pages with the arrows. Choose Smaller file, Recommended or High quality. Recommended is the default and suits most documents. To convert only some pages, pick Odd, Even or Custom under Pages to convert.
- 3
Press Convert to grayscale
Pages are drawn, made grey and saved one at a time. A progress bar shows how far it has got.
- 4
Download the result
Press Download PDF to save the file ending in -grayscale.pdf. The result screen shows the old and new file size. Your original is not changed.
Why use PDFToolz for this
No colour left anywhere
Text, photos, charts and backgrounds all become grey, so the PDF looks black and white on every screen and printer.
Runs on your device
Pages are converted by JavaScript in your browser, so reports and personal files are never sent anywhere.
Three quality levels
Pick a smaller file for email or a sharper one for printing.
No page limit
There is no account, watermark or cap on pages. Long documents take longer to finish.
Choosing an output quality
Each page is drawn as an image at a set resolution and saved as a JPEG. Higher settings keep small text sharper and make the file larger.
- Smaller file: 110 DPI with strong JPEG compression. Fine for email and screens. Small print may look soft.
- Recommended: 150 DPI with medium compression. Clear body text at a sensible size.
- High quality: 200 DPI with light compression. Best for printing and fine detail, with a larger file.
What changes when a PDF turns grayscale
To be sure no colour is left, the tool turns each converted page into a picture and rebuilds the PDF from those pictures at the original page size. Pages you leave out of the conversion are copied as they are. That has side effects.
- Text can no longer be selected or searched. Run the grayscale file through OCR PDF to get that back.
- Links, bookmarks, form fields and document properties are dropped from converted pages. If the PDF has filled-in fields, run Flatten PDF first so the answers become part of the page.
- Colour scans and photo-heavy files often get smaller. Text-only PDFs from Word or Google Docs can get larger, because sharp vector text is replaced by images.
Grayscale PDF or your printer's black and white setting
To save colour ink on your own printer, the grayscale option in the print dialog is enough. It leaves the file alone and keeps text selectable. Convert the PDF itself when someone else will print it, when a portal requires grayscale files, or when you want to see how charts look in mono.
Grey levels follow how bright each colour looks to the eye. Green comes out lightest and blue darkest. Red and green lines of similar brightness can end up nearly the same grey, so check charts after converting. If the file is too big, run it through Compress PDF.
Frequently asked questions
Add the PDF, pick a quality, press Convert to grayscale and download the result. It is free, has no page limit, and the file never leaves your device.
No. Each page becomes a grey image, so text cannot be selected or searched. Run the result through OCR PDF if you need searchable text.
Often, not always. Colour scans and image-heavy PDFs usually shrink. Text-only documents can grow because their text becomes images. The result screen shows both sizes.
Not quite. Grayscale keeps shades of grey, so photos and shading stay visible. Pure 1-bit black and white is not offered.
Yes. Under Pages to convert, pick Odd, Even or Custom and enter pages such as 2-4, 7. Only those pages turn grey; the rest are copied in colour, unchanged.
Last reviewed . See how we build and test our tools, or report an error.
