How does PDF compression reduce file size?

PDF compression reduces file size by re-compressing embedded images, removing redundant internal data, and optimizing the PDF structure. The degree of reduction depends on how much image content the PDF contains.

Will compression affect text readability?

Text in PDFs is stored as vector data and is typically unaffected by compression. Image quality may reduce slightly depending on the compression level you select.

How much can I reduce the file size?

PDFs with many large embedded images can often be reduced by 50-80%. PDFs with mostly text and minimal images may only compress 10-20% since text is already stored efficiently.

Is this useful for compressing scanned documents?

Yes. Scanned PDFs are essentially image files wrapped in PDF format and typically respond well to compression, often significantly reducing file size for sharing by email.

PDF Tool

Compress PDF

Reduce your PDF file size by removing redundant objects and optimizing internal structures.

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Compress PDF

Drop a PDF here or click to browsePDF up to 30 MB

How it works

PDF Compression

This tool re-processes the PDF to remove redundant objects and optimize internal streams. Compression results vary — PDFs with embedded images may see smaller reductions than text-heavy files.

Removes orphan objects
Compresses content streams
Preserves all content and formatting

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Tool guide

How to merge PDF files

Use the PDF merger to combine separate PDF files into one cleaner document for applications, reports, receipts, or document sharing.

Last updated: June 5, 2026

Maintained by: Chhun Menghong

Recommended workflow

Upload the PDF files you want to combine and arrange them in the final reading order.
Merge the files, then open the result to check page order, orientation, and completeness.
Download the final PDF and keep the original files until the merged version is verified.

Before relying on the result

Do not upload confidential, legal, medical, banking, or identity documents unless you are comfortable processing them in a browser tool.
Check file size limits before sending the merged document by email or through an online form.
Use authorized documents only and keep required signatures or stamps intact.

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Help & answers

Frequently Asked Questions

Important disclaimer: Alexonic Tools is completely free to use. There is no charge, and we do not save tool inputs or generated results. We value customer privacy and keep building and fixing each day. Always verify important financial, payroll, legal, tax, business, or production-code results before relying on them. If you see an issue, need a tool, or require an update, send feedback to the developer.