How do I compress a PDF file?

Drop the PDF, pick Low / Medium / High compression, and click Compress. We show you the before-and-after size so you can confirm the reduction before downloading.

Will compressing reduce PDF quality?

Text and vector graphics stay sharp because they're not rasterised. Embedded images are kept as-is by this tool — for heavy image-based PDFs, also try our image compressor on the source images.

How can I compress a PDF for email?

Most email providers accept attachments up to about 25 MB. Pick High compression first; if it's still too large, split the PDF and send it in two emails.

Why is my PDF still large after compression?

PDFs that already have compressed images or have been optimised before may shrink very little. The biggest savings come from PDFs that include embedded fonts, unused objects or uncompressed streams.

Can I compress a scanned PDF?

Scanned PDFs are essentially images. They compress modestly here — for big savings on scans, lower the resolution of the original scan or run the images through our image compressor first.

What compression level should I choose?

Start with Medium. Use Low when quality is paramount; use High to squeeze the smallest possible size out of a sharable PDF.

Is PDF compression safe?

Yes. Your PDF never leaves your device, so even confidential or legal documents are safe to compress here.

Can I compress PDFs on Mac/Windows?

Yes. The tool runs in any modern browser on macOS, Windows or Linux.

Can I compress PDFs on my phone?

Yes. Drop a PDF from your phone's Files app and download the compressed result. Works on iPhone and Android.

How do I reduce PDF size without losing readability?

Pick Medium compression — it removes structural overhead and unused objects without rasterising text, so readability is identical to the original.

Compress PDF

Shrink a PDF for email or upload. Pick a compression level and see the before/after size.

Quick answer: Compress PDF: shrink a PDF for email or upload. Pick a compression level and see the before/after size. Runs entirely in your browser, free, no signup.

Last updated 2026-05-01

Good to know

Most oversized PDFs are heavy for one reason: images saved at far higher resolution than any screen needs. Compression resamples those images and strips structural overhead, which is why a bulky scan can shrink dramatically while the text stays perfectly sharp. If your goal is to slip under an email attachment cap, our guide to compressing a PDF for email covers exactly which quality setting to pick.

Compression won't make a document editable — for that you'd convert it to another format first. If you're weighing up whether to keep something as a fixed PDF or an editable file, our PDF vs Word comparison explains when each one is the right choice. As always, your file is processed entirely in your browser and never uploaded.

Frequently asked questions

How do I compress a PDF file?: Drop the PDF, pick Low / Medium / High compression, and click Compress. We show you the before-and-after size so you can confirm the reduction before downloading.
Will compressing reduce PDF quality?: Text and vector graphics stay sharp because they're not rasterised. Embedded images are kept as-is by this tool — for heavy image-based PDFs, also try our image compressor on the source images.
How can I compress a PDF for email?: Most email providers accept attachments up to about 25 MB. Pick High compression first; if it's still too large, split the PDF and send it in two emails.
Why is my PDF still large after compression?: PDFs that already have compressed images or have been optimised before may shrink very little. The biggest savings come from PDFs that include embedded fonts, unused objects or uncompressed streams.
Can I compress a scanned PDF?: Scanned PDFs are essentially images. They compress modestly here — for big savings on scans, lower the resolution of the original scan or run the images through our image compressor first.
What compression level should I choose?: Start with Medium. Use Low when quality is paramount; use High to squeeze the smallest possible size out of a sharable PDF.
Is PDF compression safe?: Yes. Your PDF never leaves your device, so even confidential or legal documents are safe to compress here.
Can I compress PDFs on Mac/Windows?: Yes. The tool runs in any modern browser on macOS, Windows or Linux.
Can I compress PDFs on my phone?: Yes. Drop a PDF from your phone's Files app and download the compressed result. Works on iPhone and Android.
How do I reduce PDF size without losing readability?: Pick Medium compression — it removes structural overhead and unused objects without rasterising text, so readability is identical to the original.