Compress PDF

Reduce PDF file size by re-encoding pages at a quality you choose, processed locally.

Drag & drop a PDF here, or

One PDF at a time, up to 40 MB. Processed entirely in your browser.

This tool re-encodes each page as an optimized image at the quality you choose. It works best for scanned documents and photo-heavy PDFs. For PDFs that are mostly typed text, compression gains may be small and the output text will no longer be selectable/searchable — for those files, consider keeping the original.
This tool trades image quality for file size and is not guaranteed to shrink every PDF — see 'Why did my file get bigger' in the FAQ below.

How it works

Each page is rendered to an in-memory canvas using pdf.js, re-encoded as a JPEG at your chosen quality, and reassembled into a new PDF using an open-source PDF library. This is most effective for scanned documents and photo-heavy PDFs, where the original pages are already images. Nothing is uploaded — the whole process runs in your browser.

Example

A 20-page scanned PDF at 8 MB, compressed at the 'Balanced' setting, often shrinks to 2-4 MB with only a modest, hard-to-notice drop in image sharpness.

Frequently asked questions

Why did my file get bigger, not smaller?

If your PDF is mostly typed text (not scanned images), rasterizing each page into a JPEG can sometimes produce a larger file than the original, highly efficient text encoding — and you'll lose selectable text in the process. This tool shows you the before/after size so you can decide whether to keep the compressed version.

Will the text still be selectable/searchable after compressing?

No. Compression works by turning each page into an image, so the output PDF's pages are pictures of the original pages, not searchable text.

Is this a 'lossless' or 'lossy' compression?

It's lossy — image quality is traded for file size, similar to how JPEG compression works for photos.

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