How to use this PDF tool
- Select a PDF.
- Set the page or quality option needed for this task.
- Choose Compress in grayscale and review the output details.
- Download the newly created file.
#019 · PDF Compression & Optimization Tool
Grayscale PDF Compressor
Convert PDF pages to grayscale images and rebuild the document to reduce color scan size. The output preserves page proportions.
PDF Tool
Local browser processingpages
Ad space
What this tool does
Convert PDF pages to grayscale images and rebuild the document to reduce color scan size. The output preserves page proportions.
The source is parsed locally, the requested page or optimization operation is applied, and a new PDF or ZIP Blob is created for download.
Complex forms, annotations, embedded files, signatures, and encrypted PDFs may not be preserved by browser-based rewriting.
Supported formats
Input must be a standard PDF that can be opened without a password. The output is PDF, except split operations which return a ZIP containing PDF files.
| Input | |
|---|---|
| Output | PDF or ZIP |
| Processing | Local browser |
Tips for better results
- Keep a backup of the source PDF before rewriting it.
- Check small text and page orientation in the downloaded result.
- For very large documents, close other tabs to free browser memory.
FAQ
Does Grayscale PDF Compressor keep selectable text?
No. This method rebuilds each page as an image, so text selection, links, forms, and annotations are flattened.
Why can the compressed PDF sometimes be larger?
Simple or already optimized files may not shrink. The result panel shows both sizes so you can keep the better file.
Can I use this tool for password-protected PDFs?
The browser libraries cannot process a PDF that requires a password. Remove the password with an authorized tool first.
What quality setting is best for scanned documents?
Medium is a practical starting point. Use high for small print and low only when minimum file size matters more than detail.
Are my PDF pages uploaded during compression?
No. Rendering and PDF creation happen locally in your browser; only the library code is loaded from the CDN.
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Processing details
| Privacy | Local processing |
|---|---|
| Library | pdf-lib / PDF.js as needed |
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