Question 1

How does this actually shrink the file size?

Accepted Answer

Each page is rendered as an image and re-compressed as a JPEG at your chosen quality, then rebuilt into a new PDF. This works well because most oversized PDFs are bloated by large, uncompressed embedded images (common in scans).

Question 2

Will the text in my PDF still be selectable/searchable afterward?

Accepted Answer

No — this is the main tradeoff. Since every page becomes a flattened image, text can no longer be selected, searched, or copied. If you need to keep text selectable, this tool isn't the right fit.

Question 3

Will this always make my PDF smaller?

Accepted Answer

Usually, for scanned or image-heavy PDFs — but a PDF that's already small, text-only, or has already-optimized images may not shrink much, or could even grow slightly. The result always shows you the before/after size so you can decide whether to keep it.

Question 4

What quality level should I choose?

Accepted Answer

Lower quality means a smaller file but more visible JPEG artifacts. For text-heavy scans, start around 70-80% quality; for photos, 50-60% is often still visually fine.

Question 5

Is my file uploaded to a server?

Accepted Answer

No. Rendering and recompression happen entirely in your browser using pdf.js and pdf-lib — your file never leaves your device.

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Frequently Asked Questions

How does this actually shrink the file size?

Will the text in my PDF still be selectable/searchable afterward?

Will this always make my PDF smaller?

What quality level should I choose?

Is my file uploaded to a server?

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