Convert a colour PDF to grayscale
Every page is rendered, stripped of colour and rebuilt into a new PDF. It runs on your device, and you choose between 150 and 200 DPI.
- Files never leave your browser.
- No account needed
- No watermark added
- Works on any device
How it works
Step 1: Choose or drop your PDF.
Step 2: Select a resolution: 150 DPI for screens and draft prints, 200 DPI for crisper small text.
Step 3: Select PDF to Grayscale and wait while the pages are rendered.
Step 4: Download the gray copy and look through a few pages.
How the grayscale conversion works
A PDF has no single switch that turns everything gray, because colour can live in text, vector shapes and photos in different ways. So this tool takes the reliable route: it renders each page to an image at 150 or 200 DPI, drops the colour, and assembles the gray images into a new PDF with the pages in the same order.
The consequence matters. Text, lines and photos all become image content, so the words on the page can no longer be selected, copied or searched. If you need that back, run OCR PDF on the result. In return, a colour scan often gets lighter, because a gray image carries less data than a colour one.
Why use this tool
No surprise colour on paper
Print a version that is gray everywhere, so tinted backgrounds and coloured headings do not go through the colour toner.
Often lighter for colour scans
A scan saved in full colour can shrink noticeably once it is gray, which helps when a form limits upload size.
Same pages, same order
Every page is converted, one by one, so the page count and order match the original.
Processed on your device
Rendering and rebuilding happen in your browser; the PDF is not uploaded.
Common uses
Copy shops that price colour pages higher
Convert a report before printing so every page counts as black and white, whatever the original was designed in.
Colour scans of black-and-white forms
A scanner left in colour mode turned typed forms into heavy files. Grayscale conversion trims them without changing what is written.
Reading on an e-ink tablet
E-ink screens show gray tones anyway; a gray copy avoids odd-looking colour mapping and keeps files small on limited storage.
A uniform look for an archive
A dossier mixing colour and black-and-white pages can be made consistent before it is stored or handed over.
Choosing 150 or 200 DPI
DPI is the number of pixels used per inch of page. More pixels mean sharper letters and a bigger file. Because text is turned into pixels here, the choice shows up mostly in small print, such as footnotes, tables and fine forms.
- 150 DPI: fine for reading on a screen and for draft prints. Smaller output, quicker to produce.
- 200 DPI: better for small type, thin lines and fine print you expect to read on paper. Larger output, slower on long files.
- Not sure: convert at 150 DPI and zoom into the smallest text. If it is hard to read, redo it at 200 DPI.
Supported formats
- Input
- PDF files (.pdf), up to 200 MB and 2,000 pages. Password-protected files must be unlocked first.
- Output
- One PDF made of gray page images.
Pick 150 DPI for on-screen use, or 200 DPI when small print has to stay legible.
Good to know
- Text becomes part of the page image and can no longer be selected, copied or searched; run OCR PDF afterwards to add a text layer.
- Links, bookmarks and form fields are not carried into the rebuilt file, because the pages are rebuilt from images.
- A PDF that is mostly text can get larger, since sharp vector text turns into pixels.
- On phones with little memory, long documents at 200 DPI can be slow or fail; try 150 DPI or convert in parts.
Your files never leave your browser
This tool runs entirely on your device using your browser. Your files are not uploaded to our servers and are not stored anywhere. Closing the tab discards everything.
Frequently asked questions
Will the text stay selectable after converting to grayscale?
No. Pages are rendered to images and rebuilt, so the text becomes part of the picture. Run OCR PDF on the gray copy if you need selectable, searchable text again.
Does converting to grayscale make my PDF smaller?
Often for colour scans and photo-heavy files, but not always. A PDF made mostly of text can even grow, because the text is turned into pixels. Compare the sizes before you replace the original.
Should I use 150 or 200 DPI?
Use 150 DPI for on-screen reading and draft printing, and 200 DPI when small text or thin lines must stay clear. Higher DPI gives a sharper but larger file.
Is my PDF uploaded to a server?
No. The pages are rendered and the new PDF is built in your browser, so the file is not uploaded.
Can I convert only some pages to grayscale?
No, every page is converted. To keep colour on some pages, split the file with Split PDF, convert the pages you want, then join the parts again with Merge PDF.