Is Compress PDF free?

Yes. Compress PDF is free and works without an account, for files up to 25 MB and 150 pages. A free account raises that to 50 MB and 400 pages.

Are my files uploaded to a server?

Yes. Compress PDF needs server software, so the file is uploaded over HTTPS, stored privately and deleted automatically about 60 minutes after processing, or straight away if you ask.

How much smaller will my PDF get?

It depends on what is in the file. Scans and photo-heavy PDFs usually shrink the most; text-only PDFs may hardly change. You see the real before and after size, and if the result isn't smaller you keep your original.

Does compression change the text in my PDF?

No. Text and vector graphics are never altered. Only images are re-encoded, and the Medium and Strong levels lower image resolution and quality.

Can I compress a PDF to a specific size, like under 2 MB?

Yes. Choose Get it under a size, pick 200 KB, 500 KB, 1 MB, 2 MB or 5 MB, or type your own. We try the gentlest settings first and stop at the first result that fits, so the file loses no more quality than it has to. We won't take a full-page scan below about 120 dpi; if the file still doesn't fit, you get the smallest readable version and its real size, and splitting the PDF is the next step.

Does Compress PDF work on Mac, Windows, Android and iPhone?

Yes. It runs in any modern web browser, with nothing to install. Very large files work best on a desktop or laptop, because in-browser tools use your device's memory.

Compress PDF

Shrink file size by recompressing images and tidying the file structure.

Processed on our server and deleted about 60 minutes later. How we handle files

Compress PDF in short

Add a PDF, choose Light, Medium or Strong or a size to get under (such as 2 MB), and download the smaller file. Compression runs on our server, so your PDF is uploaded over HTTPS and deleted automatically about 60 minutes after processing, or straight away if you select Delete from server now. Only images are re-encoded: text, fonts and vector graphics are never changed. If the result isn't smaller, you get nothing to download and keep your original.

How to use Compress PDF

1Add a PDF.
2Pick a level, or a size to get under, such as 2 MB for an upload form.
3We process it on our server and show the before and after size.

Good to know

Results depend entirely on the file. Scans and photo-heavy PDFs usually shrink most; text-only files may barely change.
If the result is not smaller, we tell you and you can keep your original.
With a target size, the gentlest setting that fits is used. If even the strongest readable setting is too big, you see the smallest size we reached instead of a file that's been crushed.
Recompressing images is lossy at the Medium and Strong levels.
Files are processed on our server and deleted automatically. See the file-handling page.
Files are uploaded over HTTPS, processed in an isolated worker and deleted automatically. See how we handle files.

Real results on four kinds of PDF

We ran the compressor on four sample documents at each level. Photo pages and scans shrink a lot; a text-only file only gets its structure tidied; a lossless screenshot only shrinks at Strong.

Real results on four kinds of PDF
Sample (original size)	Medium	Strong
3-page office scan, 300 DPI JPEG (2.42 MB)	533 KB, 78% smaller	266 KB, 89% smaller
4 pages of large photos (12.49 MB)	3.22 MB, 74% smaller	272 KB, 98% smaller
1-page report with a PNG screenshot (2.28 MB)	Not reduced	90 KB, 96% smaller
12-page text document (26.0 KB)	13.6 KB, 48% smaller	13.6 KB, 48% smaller

Light, the lossless level, saved nothing on the scan and photo files and the same 48% on the text file. Measured on 10 October 2026 with the same code that runs on this page, using sample documents we generated ourselves.

Limits

Without an account: files up to 25 MB and 150 pages, and 2 compressions per day.
With a free account: files up to 50 MB and 400 pages, and 10 compressions per day.
A compression that doesn't make the file smaller doesn't count toward your daily allowance.
Images with transparency masks, CMYK or other non-RGB colour, or a bit depth other than 8 bits per channel are left as they are.

What happens to your file

Compress PDF uploads your file, because it needs server software. The upload is encrypted in transit, processed in an isolated worker and stored privately. The original and the result are deleted automatically about 60 minutes after processing, and you can delete them sooner from the result screen. If you'd rather your file never leaves your device, Remove pages and Split PDF also make a PDF smaller and run in your browser.

If something goes wrong

It says the file couldn't be made smaller: The file has nothing left to shrink at that level: usually it's mostly text, or its images are already compressed. Try Strong if you haven't, which also converts lossless images such as screenshots to JPEG.
Photos look soft after compressing: Medium caps images at 2,200 pixels on the long side and Strong at 1,500, with lower JPEG quality at Strong. Use Medium, or Light if image quality matters more than size.
It couldn't get under the size I picked: We stop before a full-page scan drops below about 120 dpi, because text becomes hard to read past that point. You get the smallest readable version and its real size. To get further, split the PDF or remove pages you don't need, then compress each part.
A signed PDF shows its signature as invalid: Compressing rewrites the file, which breaks certificate-based signatures. Compress before signing.
I've used up my compressions for today: The allowance resets daily. A free account raises it from 2 to 10 a day.

Guides

How to get a PDF under an upload limit and keep the text readable
Upload forms reject anything over their limit. How to hit a target size with one setting, check the text is still readable, and what to do when no setting gets there.
How to reduce PDF file size
Make a PDF smaller for email or an upload form: compress the images, cut pages you don't need, or split it. Tested figures, the attachment limits of Gmail and Outlook, and what not to bother with.
Why a compressed PDF is still too large
Compression only shrinks images, and only some of them. Tested results on scans, photos, screenshots and text show why a PDF stays big, and what to do when it's still over the limit.
How to compress a PDF on a Mac or iPhone
Shrink a PDF on a Mac with Preview's Reduce File Size filter, or on an iPhone with Shortcuts or a browser. The steps, why Preview often blurs scans, and what to use when it does.

Compress PDF: common questions

Is Compress PDF free?: Yes. Compress PDF is free and works without an account, for files up to 25 MB and 150 pages. A free account raises that to 50 MB and 400 pages.
Are my files uploaded to a server?: Yes. Compress PDF needs server software, so the file is uploaded over HTTPS, stored privately and deleted automatically about 60 minutes after processing, or straight away if you ask.
How much smaller will my PDF get?: It depends on what is in the file. Scans and photo-heavy PDFs usually shrink the most; text-only PDFs may hardly change. You see the real before and after size, and if the result isn't smaller you keep your original.
Does compression change the text in my PDF?: No. Text and vector graphics are never altered. Only images are re-encoded, and the Medium and Strong levels lower image resolution and quality.
Can I compress a PDF to a specific size, like under 2 MB?: Yes. Choose Get it under a size, pick 200 KB, 500 KB, 1 MB, 2 MB or 5 MB, or type your own. We try the gentlest settings first and stop at the first result that fits, so the file loses no more quality than it has to. We won't take a full-page scan below about 120 dpi; if the file still doesn't fit, you get the smallest readable version and its real size, and splitting the PDF is the next step.
Does Compress PDF work on Mac, Windows, Android and iPhone?: Yes. It runs in any modern web browser, with nothing to install. Very large files work best on a desktop or laptop, because in-browser tools use your device's memory.