How much smaller will my PDF get?

It depends entirely on what is in it. Colour scans shrank by 39–86% at the Balanced setting in our tests. Black-and-white scans, and PDFs that are mostly text, are already close to as small as they can be and may only lose a few percent — there is nothing there to compress.

Will the text still be selectable?

Yes. Pages are never turned into pictures of themselves, which is what some compressors do to get a bigger number. Only the images embedded in the pages are recompressed, so text stays selectable, searchable and sharp at any zoom.

Which compression level should I choose?

Balanced for almost everything — images come down to screen resolution, which is indistinguishable on a monitor. Strong when the file has to be small and will only ever be viewed on screen. Light when the document will be printed and the images need to stay at print quality.

Are the page count and page sizes changed?

No. Every page stays, in order, at exactly its original dimensions and orientation. The result is checked against the original page count before it is returned, and the job fails rather than hand back a document with a page missing.

Why did my PDF come back the same size?

Because compressing it would have made it bigger, which happens with a document that has already been through an optimiser. Rather than return a larger file, the original is handed back unchanged and the result says so. A stronger setting will usually still find something.

Is anything removed from the document?

Document properties — author, title, keywords and the application that produced it — are dropped, both because they are bytes and because they are often more revealing than people expect. Page content, bookmarks and links are kept.

Is this converter free?

Yes. Every conversion on ConvertNicely is free to use, with no account, no watermark on the result and no limit on how many files you convert.

What happens to my files?

Your uploaded file is deleted from our servers the moment the conversion finishes, whether it succeeded or failed. The converted result is deleted automatically one hour later, and you can delete it yourself at any time with the Delete button.

Is there a file size limit?

Files up to 95 MB are accepted for this conversion. Larger limits apply to paid plans in future, but the free limit is generous enough for the overwhelming majority of PDF conversions.

Do I need to install anything?

No. ConvertNicely runs entirely in your browser and on our servers, so there is nothing to download or install. It works the same on Windows, macOS, Linux, Android and iOS.

Does it work on a phone?

Yes. The whole site is built mobile-first, so you can upload from your camera roll or files app, convert, and download the result without leaving your browser.

Free

Compress PDF Files

A PDF that will not attach, will not upload, or takes forever to send is almost always big because of the images inside it — a scan at printer resolution, or photographs saved at full quality. This recompresses those images and rewrites the file more efficiently, leaving the pages themselves alone. Text stays text: still selectable, still searchable, still sharp when printed.

Also known as: PDF compressor · reduce PDF size · make a PDF smaller

Files up to 95 MBTypically under a minute

Drop your file hereor choose a file from your devicePDF · up to 95 MB

Encrypted upload · deleted right after conversion

Your files are deleted automatically

Uploads are removed as soon as processing finishes, and converted files are deleted after 1 hour. Read our privacy policy.

How to compress PDF files

Step 1
1. Add your PDF file
Drag your PDF file into the box, or choose it from your device. It can be up to 95 MB.
Step 2
2. Choose your settings
Adjust Compression (Balanced), or keep the starting values in brackets, which suit most files.
Step 3
3. Press Compress PDF
The work happens on our servers, and you can follow its progress.
Step 4
4. Download your PDF file
Your upload is already deleted, and the result is deleted after one hour.

Worth knowing

The saving comes from the images inside the document, so a PDF that is mostly text is already small and will barely change. Image quality is genuinely reduced — Light keeps print quality, Strong is for files that only need to look right on screen. A document that is already compressed is returned unchanged rather than made bigger. Document properties such as author and title are removed. Password-protected PDFs are refused; Unlock PDF removes the password first (a PDF that only restricts printing or copying unlocks without one).

Why compress PDF files?

Getting a document under an email or upload size limit
Shrinking a scanned contract or form before sending it on
Making a report light enough to publish on a website
Freeing up space in an archive of scanned paperwork

What changes

What compress PDF files changes, and what it leaves alone
Property	Before	After
Pages	Original	Unchanged
Page size	Original	Unchanged
Text	Selectable	Still selectable
Images	Original resolution	Downsampled to the level you choose

Frequently asked questions

Page updated 3 October 2026

All PDF converters

Compress PDF Files

How to compress PDF files

1. Add your PDF file

2. Choose your settings

3. Press Compress PDF

4. Download your PDF file

Why compress PDF files?

What changes

Frequently asked questions

Merge PDF

Split PDF

Compress Image

PDF to JPG

Compress PDF Files

How to compress PDF files

1. Add your PDF file

2. Choose your settings

3. Press Compress PDF

4. Download your PDF file

Why compress PDF files?

What changes

Frequently asked questions

How much smaller will my PDF get?

Will the text still be selectable?

Which compression level should I choose?

Are the page count and page sizes changed?

Why did my PDF come back the same size?

Is anything removed from the document?

Is this converter free?

What happens to my files?

Is there a file size limit?

Do I need to install anything?

Does it work on a phone?

Related conversions

Merge PDF

Split PDF

Compress Image

PDF to JPG