Compress PDF files
Make your PDF smaller for email and uploads by recompressing and downscaling its images – directly in your browser.
Your files never leave your deviceDrop a PDF file here or click to select
Works best with scanned documents and PDFs that contain photos
No Saving Possible
How to Compress a PDF in 3 Steps
Select Your PDF
Drag and drop the PDF into the upload box or choose it from your device. Nothing is uploaded.
Choose a Level
“Recommended” suits most documents. Pick “Strong” for the smallest file or “Light” to keep everything lossless.
Compress & Download
Click “Compress PDF”. The smaller file is downloaded right away and you see how much space you saved.
How PDF Compression Works
In most large PDFs, the file size comes from images: scanned pages, photos and screenshots stored at a much higher resolution than needed on screen or in print. PDFs.app finds these images, scales them down to a sensible resolution and saves them again as JPEG. Text, vector graphics, fonts, links and form fields are left untouched, so the document stays sharp and searchable.
- Light – lossless clean-up: the file is rewritten with compressed object streams, uncompressed data is packed and unused objects, thumbnails and XMP metadata are removed. Images stay exactly as they are.
- Recommended – everything from Light, plus images are re-encoded as JPEG (quality 72%) and limited to about 150 dpi or 2000 pixels on the long side. Ideal for email and sharing.
- Strong – images are limited to about 100 dpi or 1200 pixels and saved at quality 50%. Good for screen reading and strict upload limits.
- Convert pages to images – each page is rendered as one JPEG. This gives the smallest files for scans but removes selectable text.
If a PDF is already well optimized – for example a text-only document exported from a word processor – the compressed version may not get smaller. In that case PDFs.app tells you so and you can simply keep your original.
Frequently Asked Questions about Compressing PDFs
How much smaller will my PDF get?
It depends on the content. Scans and PDFs with large photos often shrink by 50–90%. Documents that contain mostly text and vector graphics are usually already compact and shrink only a little.
Will compression reduce the quality?
Light compression is lossless. Recommended and Strong re-encode images as JPEG at a lower resolution, which is barely visible on screen at Recommended. Text and vector graphics are never rasterized unless you choose “Convert pages to images”.
Will the text in my PDF still be selectable?
Yes. Only images are recompressed, so text stays selectable and searchable. The only exception is the optional “Convert pages to images” mode, which turns every page into a picture.
Can I compress password-protected PDFs?
Encrypted PDFs have to be unlocked first. Open the file with your password in a PDF reader, save a copy without protection and compress that copy.
Are my files uploaded to a server?
No. The compression runs entirely in your browser using JavaScript, so your documents never leave your device.