Grayscale PDF
Convert a color PDF to grayscale (black and white) for cheaper printing.
How do I convert a PDF to grayscale to print it in black and white?
Drop your PDF onto this page, pick 150 or 300 dpi and click “Convert to grayscale”: within seconds you download a copy where every color has been replaced by a shade of gray, ready to print in black and white without using color ink. The tool is free, needs no signup and has no hourly task limit, and it runs entirely in your browser, so your document is never uploaded to a server. It draws each page, converts the pixels to gray with the Rec. 709 luminance formula and rebuilds the PDF at the original page size. There is one trade-off you should know about: because every page becomes an image, the text stops being selectable and searchable, and links and form fields are lost. If you need to keep the text, this is not the right tool.
How to use Grayscale PDF
- Drag your PDF into the drop zone or click to choose it (up to 500 MB). You will see a thumbnail of the first page and the page count. If the PDF is password-protected, the tool points you to /unlock so you can remove the protection first.
- Choose the resolution: 150 dpi gives a lighter file that is fine for reading and draft printing; 300 dpi keeps small text and fine detail sharper at the cost of a bigger file. Also set the JPEG quality (low, medium or high) depending on how much the final size matters to you.
- Read the yellow notice, which reminds you that text will no longer be selectable, and click “Convert to grayscale”. A progress bar shows which page is being processed, and you can cancel and start over if you picked the wrong setting.
- Download the grayscale PDF. You will see the size before and after plus a preview of the first page. If the result is heavier than you expected, run it again at 150 dpi or low quality, or pass the file through /compress.
Common use cases
Print a color document in black and white with no surprises
Some office printers and print shops charge color by the page, or treat a page as color because of one blue mark. With the PDF already in grayscale, what you see on screen is exactly what comes out of the printer, and you do not pay color rates for a logo.
Save ink on class notes, manuals and slide decks
Highlighted notes, manuals with colored diagrams and slides with gradient backgrounds burn through cartridges fast. Converting them to grayscale before printing brings color ink use down to zero.
Check how a design reads in black and white
Before printing a flyer, an invoice or a poster, it is worth checking whether the colors are still distinguishable once hue is gone. If two different colors end up as the same gray, a chart will be unreadable on a black-and-white copy.
Prepare scans and photocopies for the archive
Contracts, receipts and case files scanned in color are heavier and gain nothing from it. Converting them to grayscale makes the files uniform and, at low or medium quality, often smaller. If the scan is text only, try /compress first.
Handle a sensitive document without uploading it anywhere
Bank statements, medical records and payslips are processed in your browser's memory. There is no middleman server and no account, so you leave no copy of your document in anyone's cloud.
Frequently asked questions
How do I convert a PDF to black and white for free?
Open the file in this tool, choose 150 or 300 dpi and click “Convert to grayscale”. It is free, needs no signup and has no hourly task limit. The conversion runs in your browser, so you do not wait for a server to process your document either.
Can I still select or search the text after converting?
No. To make sure every trace of color is gone, each page is drawn, converted to gray and saved as an image. The PDF looks the same, but the text is no longer selectable or searchable, and links and forms are lost. This tool does not offer a vector conversion that keeps the text.
Is grayscale the same as pure black and white?
No. Grayscale keeps the in-between tones (up to 256 gray levels), while pure black and white uses only two values and loses detail. This tool produces grayscale, which is what most printers treat as “print in black and white”.
What formula does it use to turn color into gray?
Rec. 709 luminance: gray = 0.2126 × red + 0.7152 × green + 0.0722 × blue. It weights each channel by how sensitive the human eye is to it, which is why pure red becomes a dark gray (54 out of 255) and pure green a light one (182 out of 255).
Why is my grayscale PDF bigger than the original?
A text-only PDF is tiny because it stores letters, not pixels. Turning every page into an image makes the file grow, especially at 300 dpi and high quality. Try 150 dpi with low or medium quality, or shrink the result with /compress. To print several pages per sheet and save paper, see /pages-per-sheet, and to build a folded booklet, /booklet.
Is my PDF uploaded to a server?
No. The whole process runs in your browser with JavaScript: neither the file nor the converted pages ever leave your device. Once the page has loaded you can even go offline and keep converting.