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PDF to Black & White — Convert Color PDFs in Your Browser

Convert color PDFs to pure black & white (1-bit threshold). Runs entirely in your browser with no uploads, no accounts, no limits.

● LOCAL · DOCS NEVER LEAVE DEVICE0 network requests from tools since page load

Drop your PDF here

or click to browse (max 100 MB)

Convert a PDF to B&W

Converting a PDF to black & white is the most aggressive color reduction you can do: every pixel becomes either black or white, with a hard threshold at the mid-point of the luminance range. This is ideal for documents that will be printed on a monochrome laser printer, archived in systems with strict file-size budgets, or displayed on e-ink screens where grayscale dithering is handled by the display hardware.

The tool works by walking the PDF page by page, extracting every embedded image, drawing each image onto a canvas, and applying the threshold function — luminance above 128 becomes white, below 128 becomes black. The text layer is preserved and re-written into the output, so the resulting PDF is still searchable. The output encoding is JPEG at 92% quality, which for a binary image creates very compact files.

For a more nuanced result, use the grayscale tool instead — it keeps 256 shades and produces gentler transitions. If you need some pages in color and others not, use the selective color page filter tool.

How to use

Drop a PDF
Drag a .pdf file into the drop zone, or click to browse. Up to 100 MB; the file is read locally and never leaves your device.
Automatic conversion
Once you drop the file, the tool immediately begins converting every embedded image to 1-bit black & white using a median threshold. Progress updates show which page is being processed.
Download the result
When conversion completes, the page count, re-encoded image count, and file-size change are displayed. Click Download and the black & white PDF is saved to your device.

Frequently asked

What is the difference between black & white and grayscale?

Grayscale preserves 256 shades of gray; this tool converts to pure 1-bit black & white — every pixel is either black or white, like a thresholded photocopy. It produces the smallest file size but loses all tonal information.

Will text be searchable after conversion?

Yes. The tool extracts the text layer from the original PDF and re-writes it as selectable text in the output. Embedded fonts are replaced with Times Roman, so text alignment may shift slightly.

What about scanned PDFs?

For scanned PDFs without a text layer, the scanned images are thresholded to black & white but the output won't contain selectable text. Run an OCR pass first if you need searchable text.

Will the output file be smaller?

Usually yes — often much smaller. Re-encoding images as 1-bit nearly always reduces their byte size significantly compared to full-color JPEGs. The savings are most dramatic on PDFs with photos or color graphics.

Are form fields, annotations, and vector graphics preserved?

No. The rebuild is a flat rendering — form fields, JavaScript, annotations, embedded fonts, and digital signatures are dropped. For those workflows, use a different tool that edits the original PDF stream.

Limitations

Lossy thresholdingEvery embedded image is thresholded to 1-bit. Photos with smooth gradients will show harsh banding and loss of detail. This is not a good choice for preserving photographic quality.
Vector graphics are flattenedCharts, CAD drawings, and vector content are rasterised during rebuild. The output is no longer resolution-independent.
No form fields or annotationsForm fields, JavaScript actions, embedded fonts, layers, and digital signatures are dropped during the rebuild. The output is a flat document.
Not a substitute for OCRIf the source is a scanned PDF without a text layer, the text in the output won't be searchable. Run an OCR pass first.

Platform notes

macOS: Works in Safari 16+, Chrome, and Firefox. macOS Preview can save PDFs as black & white through the Quartz filter, but this tool gives you per-image threshold control and is faster for large documents.
Windows: Edge and Chrome both support the canvas-based conversion. Adobe Acrobat Pro has a preflight tool that can convert to grayscale but not to pure 1-bit black & white.
Linux: Runs in any modern browser. On the command line, Ghostscript with -sColorConversionStrategy=Gray gets you grayscale, not 1-bit; ImageMagick's -threshold can do 1-bit but requires extracting and re-inserting every image.
iOS: Safari on iOS 16+ supports the re-encoding pipeline. On older iOS, the canvas API may reject very large images and the tool falls back to the original image data.