Convert PDF to Grayscale
Convert a color PDF to black & white grayscale — ideal for printing and reducing ink usage
Drop a PDF here
Select a PDF to convert to grayscale
Max file size: 100MB
100% Private: All processing happens in your browser. Your files never leave your device.
This tool takes a single PDF (up to 100 MB) and turns every page black and white, entirely in your browser. It opens the file with pdf.js, draws each page onto a canvas at a resolution you pick, averages each pixel's red, green and blue values into one gray value, then hands the result to pdf-lib to build a brand-new PDF. The Output Quality picker sets how sharp that render is before the color math runs: 1x (72 DPI, labeled Draft), 2x (144 DPI, Standard), 3x (216 DPI, High) or 4x (288 DPI, Ultra), with the UI itself warning that a higher setting means a sharper but larger result.
The honest limit worth knowing before you convert: a page is captured as a picture of itself, then that picture (a JPEG) is embedded into the output PDF. So even if your original PDF had real, selectable text, the grayscale copy does not — there is nothing left to select, search, or copy on any page, because every page is now an image. There is also no per-page control; pressing Convert applies to the whole document, and an encrypted PDF is turned away at the upload step rather than partway through the conversion.
How it works
1. Drop a PDF here
One file, up to 100 MB. If the PDF is encrypted, loading it stops right away with a message pointing you to the Unlock PDF tool, since an encrypted file loads with zero readable pages.
2. Pick an Output Quality
Choose 1x through 4x (72 to 288 DPI). This sets the resolution each page is rendered at before it's converted to gray and re-saved as an image — it does not change anything else about the process.
3. Press Convert
The button reads “Convert N Page(s) to Grayscale.” A progress bar tracks it page by page with the label “Converting to grayscale... X%.”
4. Download the result
Once it reports “Grayscale conversion complete!” alongside the new file size, press Download Grayscale PDF. The filename keeps your original name with “-grayscale” added before .pdf.
When you'd use it
Printing lecture notes or assignments cheaply
Sending a color PDF to a shared or personal printer in black and white first avoids burning through color ink cartridges on pages that only need to be readable, not colorful.
Meeting a black-and-white scan requirement
Some government or institutional forms specifically ask for a plain black-and-white copy of an annexure or supporting document rather than a color scan.
Archiving old color scans consistently
Converting a batch of old color scans to a uniform grayscale look before filing them away keeps an archive visually consistent, since scanners rarely produce identical color tones over the years.
Stripping distracting color before sharing a draft
A document with color-coded highlights or branded headers can be converted to a plain black-and-white copy before it goes to an audience that doesn't need to see the color-coding.
What actually happens to each page
Nothing in this tool works at the level of PDF text objects or vector graphics. Every page is rendered to an on-screen canvas first, exactly the way a PDF viewer would draw it, then a loop reads every pixel and replaces its red, green and blue channels with a single luminance-weighted gray value. That flattened canvas is then compressed as a JPEG and placed into a fresh PDF page sized to match. It's a picture of the page, not the page's original content redrawn in gray.
Because of that, there's exactly one grayscale method here — a fixed luminance formula, not a toggle between different black-and-white looks. If you wanted a sepia or tinted effect instead, that's a different kind of tool; this one only produces the one type of grayscale conversion.
Choosing an Output Quality setting
For plain text documents — letters, forms, lecture notes — Draft or Standard is usually enough, since text stays legible at 72 or 144 DPI once it's flattened to gray. Reserve High or Ultra for pages with photos, diagrams, or fine detail you want to still make out after the conversion, and expect the file to grow accordingly: a higher render resolution means a bigger canvas, which means a heavier JPEG on every page of the output.
What this tool won't do
There's no way to convert only some pages and leave others in color — Convert always processes the entire document at the setting you picked. And because color information is discarded pixel by pixel during the render, there's no undo built in; if you need the original back, you'll need your original color file, not the grayscale output.
Frequently asked questions
Will the text in my PDF still be selectable after converting?
No. Every page becomes a JPEG image of itself during conversion, so nothing on the page — including text that was selectable in the original — can be selected, searched, or copied in the grayscale download.
What do the four quality options actually change?
They set the resolution (72, 144, 216 or 288 DPI) each page is rendered at before the grayscale math and JPEG compression run. A higher number means a sharper but larger output; it doesn't change anything else about how the conversion works.
Can I convert only some pages to grayscale?
No. Pressing Convert always processes every page in the document at the quality setting you've chosen — there's no page range or selection option.
Does converting to grayscale make my file smaller?
Not necessarily. Every page is rebuilt as a JPEG at the resolution you pick, so the output size tracks your Output Quality choice far more than it tracks how colorful the original was — a low setting can shrink a file, a high one can grow it.
Will an encrypted PDF work with this tool?
No. Loading an encrypted file returns zero readable pages, and the tool stops immediately with a message telling you to unlock it first with the Unlock PDF tool, before any conversion is attempted.
What's the largest PDF I can convert to grayscale?
100 MB. Anything larger is rejected the moment you try to drop or select it, before the file is even read.