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Compress PDF files without uploading them

Make PDFs small enough to email, upload to a portal or send in a chat. Compression runs on your own device, so your documents never leave your phone or computer.

Your PDF is processed on this device and never uploaded. We don't see, store or log your files.

How it works

  1. Tap Choose file, or drop a PDF onto the page.
  2. Pick a level: Balanced keeps text crisp and photos clear; Strong squeezes images harder for the smallest file.
  3. Wait while the PDF is compressed on your device. Large files can take a minute on a phone.
  4. Check the new file size, then tap Download or Share to save it.

Why compress PDFs here

Most online compressors upload your file to their servers. This tool does the work in your browser instead: the PDF is read, optimized and saved on your device, and nothing about its contents is sent anywhere.

There is no account, no watermark and no limit on how many files you compress.

How much smaller will my PDF get?

It depends on what is inside. Scanned documents and PDFs full of photos usually shrink the most, often by 50–90%, because their embedded images are re-encoded at a lower resolution and quality. PDFs that are mostly text or vector drawings are already compact and typically shrink by only 5–20%.

Useful targets: Gmail attachments are limited to 25 MB and Outlook.com to 20 MB, and many job, school and government upload forms accept 2–5 MB. Images at 150 DPI look sharp on screens; keep 300 DPI if the document will be printed.

Limits to know about

Password-protected PDFs can't be compressed until the password is removed. Very large files need a lot of memory, so on older phones they may fail; a laptop or desktop handles them more reliably.

Text, fonts and vector graphics are kept exactly as they are. Only photos and scans are re-encoded, so they can look slightly softer at the Strong level.

Frequently asked questions

Is it safe to compress confidential PDFs here?

Yes. The file is processed entirely in your browser and is never uploaded, so it stays on your device. We don't receive your file, its name or its contents.

Will compression reduce the quality of my PDF?

Text, fonts and vector graphics are untouched. Only embedded images are re-encoded, so photos and scans may look slightly softer, especially at the Strong level. Choose Balanced when image quality matters.

Why did my PDF barely get smaller?

If a PDF is mostly text, or its images were already compressed, there is little left to remove. Savings are largest for scans and photo-heavy documents.

Does it work on iPhone and Android?

Yes. It works in Safari, Chrome and Samsung Internet on phones and tablets. After compressing, tap Share to save the file to Files or Google Drive, or send it straight to a chat.

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