Compress a PDF
Drop a PDF, pick a compression level, and download a smaller file. It works by re-encoding the document's embedded images at a lower quality — the right lever for photo- and scan-heavy PDFs. Everything runs in your browser; the file is never uploaded.
How the compression works
Most of the weight in a large PDF is its embedded images. This tool finds the document's embedded JPEG images, re-encodes each one at the quality level you choose — and downscales any that are larger than needed — then rebuilds the PDF with the smaller images in place. Your text, fonts, and vector graphics are reproduced exactly: they are not rasterized or altered, so the text stays selectable and sharp.
The three levels trade size against fidelity. Smaller file compresses hardest and caps image resolution tightest; Balanced is the sensible default — a clear reduction that looks clean on screen; Better qualitykeeps the most detail for a gentler, but still real, reduction.
When it falls back to rasterizing
Some PDFs carry their images in formats that can't be safely re-encoded in place — non-JPEG rasters, palette or CMYK images, or 1-bit scanned pages. If re-encoding the JPEGs doesn't meaningfully shrink such a file, the tool falls back to rendering each page to a compressed image at the chosen level's resolution and rebuilding the PDF from those page-pictures. This reliably reduces a stubborn scanned document, but it has a real tradeoff: the page becomes a flat image, so its text is no longer selectable or searchable. It is only used as a last resort, when in-place re-encoding couldn't help.
Either way, the tool never returns a file larger than the one you gave it, and the before/after size is shown exactly as it came out — a PDF that is already compact, or whose images can't be re-encoded, may shrink only a little or not at all.
Is it private?
Yes. The compression is browser APIs running on your own machine. Nothing is uploaded, stored, or seen by us — there is no server to send files to.
Frequently asked questions
- How does the compression make a PDF smaller?
- Most of the weight in a large PDF is its embedded images. The tool finds the embedded JPEG images, re-encodes each one at the quality level you choose, and downscales any larger than needed, then rebuilds the PDF with the smaller images in place.
- Will my text stay selectable after compressing?
- In most cases, yes. Text, fonts, and vector graphics are reproduced exactly, so the text stays selectable and sharp. The exception is the rasterizing fallback, used only when in-place re-encoding cannot help, which turns a page into a flat image and makes its text no longer selectable or searchable.
- Are my files uploaded to a server?
- No. The compression runs on your device using browser APIs. Your PDF is never sent anywhere, and there is no server to send files to.
- Is it free, and do I need an account?
- It is free with no sign-up. Drop a PDF, pick a compression level, and download a smaller file. The tool never returns a file larger than the one you gave it.