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This compressor is designed for scans and image-heavy PDFs where page images account for most of the file size.
PDF Tool
Compress PDF Online
Reduce image-heavy PDF files with a clear quality and size tradeoff.
Local browser processing
Files stay on your device
No account required
How PDF compression works
Reduce PDF file size in your browser with adjustable image quality, a target size estimate, and private local processing.
Adjust the output
Choose a compression strength or enter a target size. The page samples the document to estimate the output before processing.
Create the PDF
Compression renders each page as an optimized image. This can reduce size, but searchable text, links, and form fields become part of the page image.
Private browser processing
The complete compression workflow runs locally and does not send the source document to a remote server.
Reduce PDF size without guessing
PDF compression is a tradeoff between file size and page clarity. This browser tool is most effective on scanned or image-heavy documents because it rebuilds each page from an optimized image.
Choose compression strength by use case
Use a lighter setting for contracts, diagrams, and small text. Stronger compression is better suited to quick previews, email attachments, and documents that are mostly photos.
Understand the target-size estimate
A target size helps the tool search for a practical quality setting, but it is an estimate rather than a guaranteed byte limit. PDF structure and page complexity affect the final result.
Know what flattening changes
Rendered pages keep their visual appearance, but selectable text, hyperlinks, form fields, layers, and accessibility tags become part of the page image.
Compare before replacing the original
Open the compressed file and inspect the smallest text, charts, signatures, and fine lines. Keep the original PDF when future editing or high-quality printing may be required.
Common ways to use this tool
These are practical examples of when this workflow is useful.
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Email attachments
Shrink an image-heavy PDF before sending it through a service with an attachment limit.
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Scanned documents
Reduce the size of receipts, notes, forms, and archived paperwork created by a scanner.
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Web downloads
Create a lighter reading copy for faster downloads on slower connections.
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Submission portals
Prepare a smaller copy when an application or upload form has a stated file-size limit.
Common mistakes
- Using image compression when searchable text must remain selectable.
- Expecting every PDF to become smaller.
- Choosing a very small target without reviewing readability.
Compress PDF Online FAQ
Why can text become unselectable?
This tool compresses by rendering pages as images, which flattens text and interactive elements.
Can I enter a target file size?
Yes. The estimator finds the closest setting within the supported quality range.
Will every PDF shrink?
No. Files that are already optimized may stay similar in size or become slightly larger.
What compression level should I choose?
Start with a balanced setting and inspect the result. Use lighter compression when the PDF contains small text or detailed diagrams.
Is the target PDF size guaranteed?
No. The target is an estimate used to choose a quality level; the exact output depends on the document.
Does PDF compression remove pages?
No. It rebuilds the same page sequence at a different image quality.
Can I compress a password-protected PDF?
Only if the browser can open it. Remove the password or encryption first when the file cannot be read.