Optimize
Convert PDF to Grayscale
Turn a color PDF into clean black-and-white pages.
Processed locally — your files never leave your device
How to use Grayscale PDF
- 1
Open your color PDF.
- 2
Choose the output resolution and quality.
- 3
Click Convert to grayscale.
- 4
Download the black-and-white version.
About this tool
Color ink costs roughly ten times more than black, and laser color prints cost several times a mono page — so printing a 60-page color deck in grayscale is real money saved. Converting the file itself (rather than trusting the printer dialog) guarantees the result, previews accurately, and usually shrinks the file too.
The conversion renders each page and maps every pixel to its perceptual luminance — the same weighting your eye uses, so blue headings come out darker than yellow highlights, and photographs keep their natural contrast rather than going muddy.
Beyond printing, grayscale conversion is the standard prep for archival systems that require it, a fix for documents with distractingly colorful highlighting, and a complement to compression — combine both in the Compress tool's grayscale toggle if size is the primary goal. As with compression, pages are re-rendered as images, so text selectability is traded away.
Frequently asked questions
Why convert the file instead of just printing in black and white?
Printer grayscale settings vary and can't be previewed or shared. A grayscale file prints consistently anywhere, can be checked before printing, and is usually smaller to boot.
Will photos look right in grayscale?
Yes — conversion uses perceptual luminance weighting, the same standard used in photography, so tonal relationships and contrast are preserved naturally.
Does this reduce file size?
Usually, often substantially for colorful scans — grayscale image data compresses better than color. For maximum size reduction, use Compress PDF with its grayscale option.
Is the text still selectable afterwards?
No — pages are re-rendered as grayscale images. If you need selectable text in a grayscale document, run OCR on the result.