PDF Compressor

How to use the PDF Compressor

Drop in the PDF you want to shrink.
Choose Light to keep text selectable, or Strong for a much smaller file where pages become images.
Press Compress PDF and compare the before and after sizes before downloading.

Why PDF compression is not one thing

A PDF is a container. Its size can come from embedded fonts, vector drawing instructions, scanned page images, metadata, or leftover objects from previous edits. There is no single operation that shrinks all of them, which is why "compress PDF" means different things in different tools — and why results vary so much between them.

This tool is explicit about which operation it is performing, because the trade-off matters more than the number:

Light rewrites the file structure: unreferenced objects are dropped and the remainder is packed into object streams. Nothing is re-rendered. Text, vectors and images survive exactly. The saving is real but modest.
Strong renders each page to a bitmap and rebuilds the document around those images. The saving can be dramatic on scans, and the cost is that the page becomes a picture.

What Strong mode costs you

Rasterising is not a compression setting — it changes what the document is. After a strong pass:

Text cannot be selected, copied or searched.
Screen readers cannot read the page, so the document is no longer accessible.
Links, form fields and annotations are gone.
Zooming in shows pixels rather than crisp type.

For a scanned document these losses are mostly theoretical — the text was already an image. For a PDF exported from a word processor, they are severe, and the file will often get larger anyway, because a page of text compresses far better as text than as a photograph of text. The tool warns you when that happens.

Getting a smaller PDF a different way

If neither mode gives what you need, the largest win is usually upstream. Export from the source application at a lower image resolution, or compress the images before placing them. A 300 dpi scan is often three times the size of a perfectly readable 150 dpi one.

Removing pages you do not need is also worth trying first — the PDF Page Extractor will pull out just the relevant section, which is frequently a bigger saving than any compression pass.

Frequently asked questions

Why did Light mode barely change the size?

The file was already optimised, or its bulk is images rather than structure. Structural compression can only remove overhead, and modern PDF exporters leave little of it.

Will Strong mode make my text blurry?

At the balanced setting, text stays readable on screen and prints acceptably. At the smallest setting it softens noticeably. Check the result before relying on it for anything printed.

Can I get the text back after Strong mode?

Not from this file — the text layer is gone. Keep your original. Recovering text from the images would require OCR, which is a different process.

Is my document uploaded?

No. Both modes run in your browser, including page rendering. Confidential documents never leave your device.

Which mode should I use for a scanned contract?

Strong, with greyscale switched on. Scans are already images, so you lose nothing that was there, and greyscale typically halves the size again.