Compress PDF
Shrink a PDF's file size by re-compressing the photos and scans stored inside it. Scanned documents and picture-heavy reports often drop by half or more, while a PDF made purely of text has almost no image data to squeeze and will barely change. The whole process runs on your own device, so even a confidential file never leaves it.
Before you start
What can this PDF compressor reduce?
This tool recompresses eligible embedded JPEG images while keeping the PDF pages and text structure. A scan can shrink considerably; a text-only PDF or a PDF containing other image formats may barely change. Photos can lose sharpness, so compare the downloaded result with the original.
For a strict email limit, follow the PDF size-limit guide. If sharp text matters more than size, split the PDF instead.
🔒 This file is processed on your device. Nothing is uploaded to any server.
How to compress a PDF
- Select your PDF file.
- AllToolsHub finds and re-compresses the embedded images.
- Download the smaller PDF.
When you'd use this
- Upload size limits — A portal refuses your scan because it caps uploads at 2 MB and your file is 9 MB.
- Email attachments — Most mail services reject attachments over roughly 25 MB.
- Phone-scanned documents — Scanning-app pages are stored as full-resolution photographs and are far heavier than they need to be.
- Slow or metered connections — Sending a large report when bandwidth is limited or expensive.
Good to know
- It compresses images, not text — The tool finds the pictures embedded in the PDF and re-saves them at a lower JPEG quality. Text and vector graphics are left completely untouched and stay perfectly sharp.
- Text-only PDFs barely shrink — If there are no photographs inside, there is nothing to compress — expect little or no change in size.
- Photo detail softens slightly — Images are re-encoded, so fine detail loses a little crispness. Keep your original if you might need the full-quality version later.
- Already-compressed files resist — A PDF that has been through a compressor once will not shrink much a second time.
Frequently asked questions
Will this work on any PDF?
It helps most with PDFs that contain photos or scanned pages. A PDF that's mostly text may barely shrink, because there's little image data to compress.
Does compressing reduce quality?
Embedded images are re-encoded at a slightly lower JPEG quality to save space. Text and vector graphics are untouched.
How much smaller will my file actually get?
It depends entirely on what is inside it. Scanned documents and photo-heavy files commonly drop by 40–70%. A text-only PDF may shrink by only a few percent, because there are no images to re-compress.
Is the text still selectable afterwards?
Yes. Only embedded images are re-encoded — the text layer is copied across untouched, so you can still select, search and copy text in the compressed file.
Why did my file come out bigger?
It is uncommon, but it happens when a PDF's images are already stored more efficiently than the re-encoding can manage. If the result is larger, simply keep your original.