Convert to Grayscale

Convert PDF to grayscale online, free: turn pages black and white to save colour ink when printing.

Converts a colour PDF to grayscale for cheaper printing, lower ink usage, or a consistent look across a batch of scans.

Several grayscale algorithms and render qualities are available, and you can limit processing to a page range. Note that grayscale conversion rebuilds pages as images, so text in text-based PDFs is no longer selectable and the file may grow larger.

Everything runs locally in your browser — nothing is uploaded to any server.

How to use

  1. Upload a PDF — Drop in the file to convert.
  2. Choose algorithm and quality — Pick the grayscale method and render scale for your use case.
  3. Convert and download — Check the result, then download the grayscale PDF.

FAQ

Why did the file get larger after converting to grayscale?

Grayscale conversion rebuilds pages as images, turning vector lines and text into bitmaps, which usually increases the size. Choosing a lower render scale helps keep it down.

Can text be copied after grayscale conversion?

No. Rebuilding the page as an image discards the text layer. If searchable text matters, prefer grayscale printing over converting the file.

Which of the three grayscale algorithms should I pick?

Luminosity (BT.709 weighting) is closest to human perception and works well in general; Average keeps more mid-tone detail; Lightness (midpoint of the lightest and darkest channels) gives softer transitions, which suits photo-heavy pages.

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