Compress PDF
Make a PDF small enough to email.
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or drag it here
One PDF file
Your files stay on your device
How to use it
Drop your PDF here to make it smaller. Keep the text sharp and selectable, or shrink scans by up to 80%. Your file stays on your device.
Most PDFs that are too big are full of images — scanned pages, photos, or screenshots. The text barely adds anything to the size.
Drop your PDF onto the box above and pick an option. Gentle keeps everything exactly as it is: the text stays sharp, selectable, and searchable, and links keep working. It saves less, sometimes very little.
Strong turns every page into a picture. For scans and image-heavy PDFs it often cuts the size by 80% or more. The catch: you can no longer select or search the text, and links stop working. On a typed, text-only PDF it can even make the file bigger.
Quick rule: scans → strong, typed documents → gentle. In strong mode you’ll see the size of the first page before you start, so you can adjust the settings.
FAQ
Which option should I pick?
Scanned or image-heavy PDF: strong. Mostly typed text that needs to stay selectable: gentle.
Why did my file barely shrink with gentle?
There wasn’t much to tidy up. Gentle never touches the pictures, so it can only save so much.
Why did my PDF get bigger?
That happens when you use strong on a text-only document. Use gentle for those.
Will the text still be searchable?
With gentle, yes. With strong, no — the pages become pictures.
Can anyone else see my PDF?
No. It’s compressed on your own device and never sent anywhere.
How it worksFor the curious
Lossless cleanup rewrites the file structure, packs objects more efficiently, and strips metadata. Nothing on the page changes, so the result stays accessible to screen readers. Savings are often between nothing and a fifth of the original size, because files from modern software are usually already well packed.
The strong method rasterises: every page is redrawn as a JPEG and the document is rebuilt around those images. Text stored as characters is extremely compact, so the same text stored as a picture of itself can be larger — which is why this mode can grow a text-only PDF.
In strong mode the preview renders page 1 at the current resolution and quality and reports its real size. The full document scales roughly with its page count from there. 72 DPI is screen resolution, 150 is readable in print, and 300 is full print quality.
Server-based compressors take a third route — re-encoding the embedded images while leaving the text layer untouched. That needs a full rewrite of the PDF content streams, which the available browser libraries cannot do, so both honest options are offered here instead.