PDF Compressor

Create a smaller JPEG-backed PDF with adjustable quality and scale controls, then compare size savings before downloading.

Last updated: March 17, 2026

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Interactive tool

The live form, validation, and result state for PDF Compressor load after the page scripts run. The content below summarizes how the tool works and links to related pages in the catalog.

Compress PDF files in the browser with scale and quality controls, before-and-after size comparison, and instant download.

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How to use PDF Compressor

1
Enter your inputs into the PDF Compressor form.
2
Adjust optional settings so the scenario matches your real-world case.
3
Review the result, then tweak one variable at a time to compare outcomes.
4
Keep your best scenario as a baseline for future decisions.

Technical utilities provide rapid validation checks and should be paired with environment-specific testing.

Best use cases

Compare realistic pdf compressor scenarios without switching between spreadsheets or separate references.

Change one assumption at a time to see how the result moves.

Use the interactive output as a quick planning baseline before deeper review.

Worked example

Scanned document compression example

A user with a scanned PDF can lower image quality and scale slightly, then compare the output size before downloading the smaller version.

Start with moderate settings rather than the lowest quality immediately.
Review the visual result before replacing the original file.
Keep the original if text readability or file size worsens.

This tool is strongest for image-heavy PDFs where a lossy tradeoff is acceptable.

Methodology

Each page is rendered and rebuilt into a JPEG-backed PDF at the chosen scale and quality settings.
The before-and-after file-size comparison shows how those rasterization settings change output size.

Tips for better results

Validate all required inputs before trusting the result.
Test at least one conservative scenario before acting on the output.
Recalculate when your assumptions, costs, or constraints change.

FAQ

How does this PDF compressor reduce file size?

The tool renders each PDF page as an image and rebuilds a JPEG-backed PDF using your selected scale and quality settings.

Will compression preserve selectable text and vector graphics?

Not always. This lossy approach works best for scanned or image-heavy PDFs and may reduce searchable text, links, or vector sharpness.

Why can some PDFs become larger after compression?

Text-first or already optimized PDFs can be smaller than a rasterized copy. If output grows, lower scale or quality, or keep the original file.

Was this tool helpful?

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Key assumptions

Scanned and image-heavy PDFs are more likely to shrink than text-first or already optimized PDFs.
The selected quality and scale settings represent an acceptable tradeoff between readability and file size.

Important limitations

Selectable text, links, vector graphics, and sharp line art can degrade because the output is rebuilt from page images.
Some PDFs may become larger after conversion if the original file is already optimized more efficiently.

Sources and validation

PDF.js Examples
Reference for the page-rendering approach used before rebuilding a new compressed output PDF.
pdf-lib: PDFDocument API
Reference for assembling the new browser-side output PDF after each page is rasterized.

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