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Compress PDF Online

Reduce file size for faster sharing and smaller archives. Shrink PDF file size with adjustable compression. Runs locally — great for email attachments and cloud storage limits.

No document data Download No Sign-up Required

01 / add file

Drop your PDF here

Choose one document to make lighter and easier to share.

Single file · Max 256 MB

Core processing stays in this browser after the page loads. Large files use device memory and may run slower.

Compress PDF Online

Shrink PDF file size with adjustable compression. Runs locally — great for email attachments and cloud storage limits.

Quick answer

How can I compress a PDF without uploading it?

Select your PDF, choose a compression level, and hit compress. The file processes in your browser so it never uploads to our servers. Savings vary by content; text-heavy PDFs often compress more than scans.

Privacy by default

Select your PDF, choose a compression level, and hit compress. The file processes in your browser so it never uploads to our servers. Savings vary by content; text-heavy PDFs often compress more than scans.

How to compress a PDF

How to compress a PDF

Three steps to a smaller file

  1. 01

    Upload your PDF

    Add a PDF to compress.

  2. 02

    Choose compression

    Pick a level that balances size and quality.

  3. 03

    Download

    Save the smaller PDF to your device.

Why use our PDF compressor?

Why use our PDF compressor?

Smaller files, same workflow

01

100% in your browser

Files stay on your device. No uploads to our servers — ideal for confidential documents.

02

No account required

Get started instantly. No registration, no credit card, no watermarks on exports.

03

Fast local processing

PDF work runs locally in your browser for quick results — no round-trip to a server.

04

Works everywhere

Use Chrome, Firefox, Safari or Edge on desktop and mobile — no install needed.

05

Privacy by design

We never store your files. Processing happens in memory in your tab.

06

Core tools free

Use without limits tied to an account — built for everyday document tasks.

PDF Compression FAQ

PDF Compression FAQ

Quality, privacy, and limits

Will compression damage quality?

High compression may reduce fidelity; use lower settings for important documents.

Is there a file size limit?

Very large files may hit browser limits — try a smaller PDF if issues occur.

Do you store my PDF?

No — compression runs entirely in your browser.

Can I compress for email?

Yes — aim for under typical email attachment limits.

Scanned PDFs?

Scanned pages may compress less than text-based PDFs.

Is it free?

Core compression is free with no account required.

Learn before you process

PDF guides for this workflow

Get the answer, understand the trade-offs, then use the focused tool when you are ready.

How to merge PDF files online

Combine PDFs in the right order, keep bookmarks and form fields, and check the result before you share it.

Read the merge guide

How to merge PDF files on a phone

Select, order, merge and verify PDFs from a mobile browser, combine photos and scans first, and avoid the memory and download problems that catch people out on phones.

Read the mobile guide

How to compress a PDF online

Reduce PDF size for email and uploads without losing quality: the three compression levels, readability checks and size-limit fallbacks.

Read the compression guide

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