Compress PDF Files Online for Free

A PDF that won't attach to an email or takes forever to upload is almost always carrying oversized images. Photos embedded at full camera resolution, high-DPI scans and un-optimised graphics can push a document into the tens of megabytes even when it's only a few pages long. PDFOrca's compressor shrinks that file back down to a practical size while keeping it perfectly readable.

Compression works by re-sampling and re-encoding the images inside your PDF and stripping redundant data the viewer never needed. Plain text and vector elements — headings, tables, line art — stay crisp because they aren't image-based to begin with. The result is a lighter file that still looks right on screen and in print.

Why file size matters

• Email limits: most inboxes reject attachments over 20–25 MB, so a bloated scan simply bounces.
• Web forms and portals: government and banking uploads frequently cap files at 2 MB or 5 MB.
• Storage and sharing: smaller PDFs sync faster and use less space across every device.

Balancing size against quality

There's always a trade-off between how small a file becomes and how sharp its images stay. For documents that are mostly text with the odd logo, aggressive compression is invisible. For photo-heavy brochures or portfolios, a lighter setting preserves detail. If a scanned document looks fuzzy after compression, the original scan resolution was probably the real culprit — try re-scanning at 200–300 DPI rather than 600.

Getting the smallest usable file

If a document is still too large after compressing, the images inside are likely enormous. Converting a photo-only PDF back through PDF to JPG and then JPG to PDF at a sensible resolution can help. When you're bundling several files, compress each one before you merge them — it's far more effective than compressing one giant merged file at the end. Scanned paperwork specifically benefits from our OCR step too, which makes the text searchable without inflating the file.