How to use the Compress PDF tool
- Select a PDF or drop it onto the box.
- Pick a level: Balanced suits most documents, Smallest squeezes the most, Best quality keeps scans sharp for printing.
- Compare the size before and after, then click Download.
Why PDFs get so large
The size of a PDF is mostly decided by the images inside it. A single page scanned at 600 dpi in colour can be several megabytes, and a phone photo turned into a PDF page is often 3–5 MB. That quickly runs into limits:
- Email attachments are usually capped at 20–25 MB.
- Upload forms for jobs, visas, universities and banks often accept only 1–5 MB.
- Messaging apps compress or reject large files.
How this compressor works
Each page is redrawn at a sensible resolution for reading and printing, and saved as an efficiently compressed image, then the pages are put back together at their original size. For scanned documents this keeps them looking the same while dropping most of the weight.
| Level | Resolution | Best for |
|---|---|---|
| Smallest | 96 dpi | Reading on screen, strict upload limits |
| Balanced | 130 dpi | Most documents, email |
| Best quality | 170 dpi | Printing, small print |
Good to know: because pages become images, text in the result cannot be selected or searched. For PDFs created from Word or similar programs that are mostly text, the original is usually small already and is often better kept as it is.
Tips for the smallest PDF
- Remove pages you do not need with Split PDF first.
- If you are creating the PDF from photos, shrink the photos with Compress Image before using JPG to PDF.
- Scan documents in greyscale rather than colour when colour does not matter.
Frequently asked questions
Which PDFs get much smaller?
Scanned documents and PDFs full of photos usually shrink by 50–90%, because their page images are often stored at very high resolution. PDFs made mostly of typed text are already small and may not shrink.
Why can't I select the text after compressing?
To make pages smaller, each page is saved as an optimised image. That works very well for scans, which were images already, but it means typed text is no longer selectable or searchable. Keep your original if you need to copy text from it.
How do I get a PDF under 1 MB or 2 MB for an upload form?
Start with Balanced. If it is still too big, choose Smallest. If that is not enough, use Split PDF to send fewer pages.
Will the compressed PDF look blurry?
On screen, Balanced and Best quality look very close to the original. Smallest is fine for reading but fine print may look soft when you zoom in.
What if the file gets bigger?
If a PDF is already compact, the tool tells you and you can simply keep the original.
Is my PDF uploaded?
No. Compression runs in your browser, so documents like bank statements and IDs stay on your device.
Guide by the ToolsYes team · Last updated