“We noticed you may be using an ad blocker. SEO Site Checker relies on ads to keep our SEO tools free. Please consider disabling your ad blocker to support us - thank you!”“We noticed you may be using an ad blocker. SEO Site Checker relies on ads to keep our SEO tools free. Please consider disabling your ad blocker to support us - thank you!”
Upload a color PDF and download a grayscale copy. Text stays selectable, images and shapes turn gray. Free, no account, no watermark.
Max file size: 60 MBUp to 2 files per uploadGet 500 MB and up to 5 files per upload, freeSign up free
Uploading your file…
0%
How to Convert a PDF to Grayscale
Quick answer: To convert a PDF to grayscale, upload it and press Generate PDF. You get a gray copy named after your file plus _grayscale. Try it with your own file.
Upload. Drop a PDF on Drop PDF File Here. Guests get 2 files up to 60 MB each, a free account 5 files up to 500 MB each.
Generate PDF. Press the button and wait for Converting to grayscale...
Download. The Result table lists each file with its Size.
Speed: a small file took about 3 seconds. Start above.
A protected file asks for its password. Without it, remove the password first with Unlock PDF.
What Happens to Colors, Images and Text
We run Ghostscript with a gray color space, as the Ghostscript pdfwrite documentation describes, and override each ICC profile. RGB and CMYK color images and vector graphics all change. The widest red, green and blue gap on our test page fell from 204 to 1.
A 750 ppi test photo stayed 750 ppi, and text stays text: 5,680 characters before and after. The result is grayscale with 256 gray levels, not monochrome two-tone black and white.
Will Converting to Grayscale Make My PDF Smaller?
Sometimes the file grows. Size in bytes, our runs on October 28, 2026:
Test file
Before
After
Change
3 page photo PDF
509,642
139,250
73 percent smaller
30 page text report
313,773
138,904
56 percent smaller
Already gray PDF
363,434
362,463
under 1 percent
2 page text PDF
2,613
6,449
2.5 times larger
12 pages, color profile photos
8,216,975
10,865,773
32 percent larger
12 pages, one photo reused
4,345,384
17,189,627
about 4 times larger
Plain JPEG photos shrink by about two thirds. A file of 6 or more pages with no bookmarks or links is converted page by page, so an image reused on every page, a logo say, is stored again each time. A 40 page test file grew 13 times. Compare the Size column with your original, and if the file grew, keep the original or use the PDF Compressor.
What It Keeps and What It Changes
The Library of Congress description of the PDF format explains what a file holds. On a 12 page test file the page count, metadata and both bookmarks survived. Form fields are flattened, and the owner password and permissions go, so re-protect with Lock PDF. A scan stays a picture; OCR PDF adds searchable text.
Limits, Privacy and Speed
A third guest file was refused. Uploads travel over HTTPS and are deleted when processing ends; the result waits two hours, so download it first.
Frequently Asked Questions (FAQs) is a list of common questions and answers provided to quickly address common concerns or inquiries.
Is the PDF to Grayscale converter free?
Yes, it is free, with no watermark and no account. Guests can convert 2 files of up to 60 MB each, and a free account raises that to 5 files of up to 500 MB each. Upload your file above.
Does converting a PDF to grayscale reduce the file size?
Sometimes. Plain JPEG photo PDFs shrank 67 to 73 percent in our tests and a text report 56 percent. A tiny text PDF, color profile photos and a long PDF repeating one image grew, so check the Size column in the Result table.
Will the text stay selectable and the layout the same?
Yes. Text becomes gray text, and 5,680 characters were extracted before and after in a text test, with the same page count. Selectable text is kept, so you can still search it. Form fields are flattened.
What is the difference between grayscale and black and white?
Grayscale keeps 256 shades of gray, so photos keep their detail, while pure black and white has only two tones and turns photos into dots. This tool makes grayscale, which suits invoices, reports or a draft print. For two-tone output, use a scanner setting.
Can I convert a password protected PDF to grayscale?
Yes, if you enter the password when the uploader asks. Without it the tool refuses and says to remove the password first with Unlock PDF; a wrong one is refused too. The result has no password, so protect it again with Lock PDF.
Why did my grayscale PDF come out larger?
We found three causes. A tiny text file gets its fonts rewritten. Photos with a color profile can come out larger. A PDF of 6 or more pages without bookmarks or links that reuses one image can grow several times. If the Size column shows a bigger file, keep your original.
What happens to my file after I upload it?
Files are processed on our server over HTTPS. We delete the upload as soon as processing ends. The converted file stays behind a random link for about two hours, then it is deleted as well, so download it before then.
We use cookies to personalize content and ads, to provide social media features and to analyze our traffic. You consent to our cookies if you continue to use our website.
Install SEO Site CheckerFree SEO tools - always in your pocket.
