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Compress a PDF and reduce file size

Shrink large PDFs by resampling images and stripping waste. Choose the balance between size and quality.

Processed on your device Free, no signup
Select PDF files

or drop them here — as many as you like

Working…

Processing your file securely.

How to use Compress PDF

  1. Add your file by dragging it onto the box above, or click to browse your device.
  2. Adjust the settings if you need something other than the defaults.
  3. Press the Compress PDF button and wait a moment while it processes.
  4. Your finished file downloads automatically. You can also download it again from the result panel.

Is it private?

This tool needs a small amount of server help to do its job. Your file is sent over an encrypted connection, processed immediately, and deleted automatically within one hour. We never read the contents, never share them, and never use them for any other purpose. Tools that can run fully offline are clearly marked as private.

What it costs

Nothing. There is no account to create, no daily limit on how many files you can process, no cap on file size beyond what your own device can handle, and no watermark added to your output. The site is funded by advertising, which keeps the tools themselves free for everyone.

Good to know

Because compress pdf happens on your own hardware, speed depends on your device rather than on how busy our servers are. A modern laptop will handle most documents almost instantly. Very large files — several hundred megabytes, or documents with thousands of pages — will take longer and use more memory, so on a phone it is worth closing other tabs first.

If a file fails to open, it is usually because it is password protected or was damaged in transit. Remove the password with Unlock PDF, or try Repair PDF to recover a corrupted document.

Frequently asked questions

Is Compress PDF free to use?
Yes, completely. There is no account to create, no trial period and no daily limit on the number of files you can process. We do not add a watermark to anything you produce.
Do my files get uploaded to a server?
This particular tool needs server processing to work. Your file is sent over an encrypted connection, processed straight away, and permanently deleted within one hour. We never read or share its contents.
Is there a limit on file size?
Files up to 500 MB are supported. If you need to process something larger, try splitting it first.
Which browsers are supported?
Any current version of Chrome, Edge, Firefox, Safari, Opera or Brave, on desktop or mobile. No plugin or extension is needed and nothing is installed.
Will the quality of my document change?
No. Unless you are deliberately using a tool that reduces quality — such as compression, where you choose the trade-off yourself — the original content, fonts and images are preserved exactly as they were.

Related tools

Other things you can do in optimise pdf.

Repair PDF

Rebuild a broken cross-reference table and recover readable content from a PDF that will not open.

Flatten PDF

Merge form fields, annotations and layers into the page so the file looks identical everywhere.