Reduce PDF file size by up to 90% while keeping text sharp and images clear. Free methods for compressing PDFs online, on Mac, and on Windows.
Large PDF files create real problems. Email providers block attachments over 25 MB. Upload forms reject oversized files. Sharing large PDFs over messaging apps is slow and eats through mobile data.
Common reasons PDFs become bloated:
The good news: most PDFs can be compressed by 50-90% without any visible loss in quality.
The fastest way to reduce PDF size is with a free online compressor:
The tool intelligently compresses images, removes unused metadata, and optimizes the PDF structure while keeping text perfectly sharp and images clear.
Mac users have a built-in option:
Mentioned in this article — free, no sign-up required.
If you have Adobe Acrobat Pro:
The "Optimized PDF" option gives you granular control over image compression, font embedding, and which elements to discard. This is the most powerful option but requires a paid subscription ($19.99/month).
PDF compression uses several techniques:
Image downsampling — reduces the resolution of embedded images. A 300 DPI image in a PDF meant for screen viewing can be reduced to 150 DPI with no visible difference. Image recompression — converts lossless images (PNG, TIFF) to lossy JPEG compression. This alone can reduce image size by 80%. Font subsetting — instead of embedding the entire font (thousands of characters), only the characters actually used in the document are kept. Metadata removal — editing history, thumbnails, and application-specific data are stripped out. Stream optimization — the PDF's internal data streams are recompressed using more efficient algorithms.Before compressing, consider these strategies:
It depends on the content. PDFs with lots of high-resolution images can be reduced by 80-90%. Text-heavy PDFs with few images may only shrink by 10-20%.
Does compressing a PDF reduce quality?Text quality is never affected — text remains perfectly sharp at any compression level. Image quality depends on the compression settings. Our tool uses smart compression that maintains visual quality while significantly reducing size.
What's the maximum PDF size I can compress?Reformat's free plan supports files up to 10 MB. Pro users can compress files up to 100 MB.
Can I compress password-protected PDFs?You'll need to remove the password first, then compress, then re-apply password protection if needed.
PDF to JPG
Convert PDF documents to JPEG Image format