What stays local
Your selected PDF is handled in this browser session. BQ PDF Tools does not add your document to the offline cache or upload it to an application server.
Optimize PDF tool
Convert PDF to Grayscale
Convert colour PDF pages to grayscale locally for monochrome printing, sharing, or scan cleanup.
Choose PDF
Processing happens locally in this browser. Keep this tab open until the result is ready.
Drop a PDF file hereor select a file from this device · adaptive limit based on this device
Settings restored for this tabNon-text options from the previous page load were restored. Files and filenames were not saved.
Leave blank for all pages.
Raster conversion: converted pages become images, so selectable text, links, forms, and accessibility structure are removed.
Choose a file to begin.
Processing did not finish
Diagnostics include the tool, browser, file count, total size, and visible error—but never filenames or document contents.Your selected files and settings are still available.
Trust and output notes
Use this quick checklist before replacing an important PDF.
What this tool preserves
- The tool explains when output becomes image-based.
- File-size results are compared before download.
- The original remains available if the new file is larger.
What to check
Compression results depend on the source PDF. Image-based modes can remove selectable text, links, forms, and accessibility information.
Practical examples
Example 1
Make a scanned PDF small enough for an upload form.
Example 2
Check colour usage before sending to a print shop.
Example 3
Reduce white margins before compressing a scan.
How to convert pdf to grayscale
Step 1
Choose a PDF and the pages to convert.
Step 2
Select the output DPI and JPEG quality.
Step 3
Create the grayscale PDF and compare readability before downloading.
What this tool does
This scan-focused conversion renders pages, removes colour information, and rebuilds the PDF with JPEG page images. Selectable text, links, forms, and accessibility structure on converted pages are lost.
Privacy note: selected files are handled by JavaScript running on your device. The application does not intentionally transfer document contents to a BQ server. Browser extensions, managed-device policies, and the browser itself remain outside the site’s control.
Compatibility note: PDF is a complex format. Very large, encrypted, malformed, digitally signed, or unusually constructed files may not process correctly. Keep the original document until you have checked the result.
Frequently asked questions
Will text remain selectable?
No. Converted pages become grayscale images. Use this tool only when that tradeoff is acceptable.
Can I convert selected pages only?
Yes. Unselected pages are copied from the original PDF.
Does grayscale always reduce file size?
Not always. The result depends on the original document and selected quality settings.
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