Compress PDF

Make a PDF smaller by re-encoding the images inside it, dropping duplicated objects and clearing metadata, without sending the document anywhere.

Drop your files here

.pdf · up to 300 MB

Choose files

How to Compress PDF

1
Drop your PDF
Add one file or up to twenty at once. Each document is opened by your own browser, so nothing is uploaded and nothing waits in a queue.
2
Pick a compression level
Best quality keeps images at 300 DPI and quality 85. Balanced goes to 150 DPI and quality 65. Smallest file drops to 96 DPI and quality 45. Or pick Target size with a goal such as 500 KB, and the quality and resolution are found for you.
3
Download the smaller file
The result keeps every page, all text and all form fields. Several files come back as one ZIP archive; each name ends in -compressed, or in the target, such as -500kb or -smallest, when you compress to a size.

What shrinks, and what cannot

Almost all of the weight in a large PDF is pixels. A scanned page stored at 300 DPI is roughly 8.7 million pixels, while the text of the same page is a few kilobytes. So compression works on the raster images: each one is re-encoded as JPEG at the quality of the level you chose, and images drawn at a higher resolution than the level allows are resampled down first. Text, fonts, vector drawings, links, bookmarks and form fields are copied across untouched, which is why a contract that is pure text usually shrinks by only a few percent, and a scanned report of the same length can lose eighty percent of its weight. Identical images repeated on many pages, such as a letterhead logo, are stored once instead of fifty times, and the document metadata is cleared unless you keep it.

Choosing between the three levels

Best quality is for documents that will be printed or read closely: 300 DPI is the print standard and quality 85 leaves scanned type crisp. Balanced is the everyday choice for email and portals, at 150 DPI, which still reads well on screen. Smallest file is for hard size limits: 96 DPI and quality 45 make photographs visibly softer, though text scans stay readable.

The document never leaves your computer

Compression runs inside your browser tab, in a background thread on your own machine. The PDF is not uploaded, not copied to a server and not stored anywhere for us to delete later, which is why contracts, payslips and medical scans can be compressed here. Close the tab and everything still in memory is gone with it.

Frequently asked questions

Why did my PDF barely get smaller?

Because it has little or no raster content. Text, fonts and vector graphics are already compressed inside a PDF and are copied over untouched, so a file of pure text has almost nothing left to squeeze. Files built from scans or photographs shrink the most.

What is the difference between the three levels?

They set two numbers: JPEG quality and the resolution ceiling. Best quality uses quality 85 and 300 DPI, Balanced uses 65 and 150 DPI, Smallest file uses 45 and 96 DPI. Lower numbers mean smaller files and softer images; page count and text are identical in all three.

Will my scanned pages look worse?

At Balanced and Best quality, scanned text stays sharp enough to read comfortably on screen and to print. At Smallest file, photographs and colour gradients show visible artefacts and fine print softens. Try Balanced first and compare before you commit to a harsher setting.

Does my file get uploaded to a server?

No. The document is parsed, re-encoded and rebuilt by your own browser. No part of it travels over the network, and nothing of yours is stored anywhere. Compression also works with the connection switched off once the engine has loaded, which happens with the first file you add.

Is the text layer still searchable afterwards?

Yes. Text is never rasterised here, so every word stays selectable, searchable and copyable, and bookmarks, links and form fields keep working. Only the embedded images are re-encoded, which is what makes the file smaller in the first place.

Why can a password-protected PDF not be compressed?

Because its contents are encrypted, and the images cannot be read without the password. Remove the protection first with the password removal tool, compress the plain file, then apply a password again if you still need one.

How small can a vector or text-only document get?

Usually a few percent at best. Such a file is mostly font data and drawing instructions, both already packed by the format itself. When there is nothing raster to work on, the tool says so plainly instead of handing back a file of the same size.

Can I compress several PDFs at once?

Yes, up to twenty files in one go, with the same level applied to each. Every document is processed separately in your browser and the results arrive together in one ZIP archive, with each file keeping its original name plus a suffix: -compressed for a level, or the target, such as -500kb, when you compress to a size.