To compress a PDF, pick a compression level, click Compress PDF, and compare the before and after size. Each page is re-saved as a lighter image, which shrinks scans and photo-heavy files a lot. The trade-off is that text is no longer selectable.
Why is my PDF too big to email or upload?
Big PDFs are almost always full of images. A scan is one photo per page, and a report with charts or pictures can pass 20 MB without much trouble. Email services often stop around 20 to 25 MB, and many upload forms set even lower caps.
Our guide on why a PDF gets so large shows how to spot the cause. For most files, compressing the page images is the fix.
How to compress a PDF
- Click Select File, or drag your PDF into the drop zone.
- Choose a level: Low keeps the best quality, Recommended balances quality and size, and High makes the smallest file.
- Click Compress PDF and check the before and after size, then click Download.
What compression does to your PDF
This tool draws each page in your browser and saves it again as a JPG image, then builds a new PDF from those images. Low renders pages at 2x with quality 85. Recommended uses 1.5x at quality 70. High uses 1x at quality 45, which is the smallest and the softest.
That approach works well on scanned documents, photos, and slide decks. Because pages become images, text you could select before can no longer be selected or searched. If that matters, keep the original too. A PDF that is already mostly plain text may also come out larger, and the tool will tell you when the result is bigger than the original.
If the file is still too big
- Try the High level, then check that small text is still readable.
- Remove pages you don't need first with Delete PDF Pages.
- If the PDF was made from photos, shrink the images before you build it. Image Compressor helps, then combine them with JPG to PDF.
- Split a very long file into parts with Split PDF and send them separately.
Frequently asked questions
How can I reduce a PDF's file size without uploading it?
Use this tool. It compresses the file in your browser, so it never goes to a server. Pick a level, compress, and download the smaller file.
How much smaller will my PDF get?
Scans and photo-heavy files often shrink by 50 to 90 percent. Mostly text PDFs shrink little, or can even grow, since there's not much image data to reduce.
Will I still be able to select and copy text?
No. Compression turns each page into an image, so the text is not selectable afterward. Keep the original if you need it. For copying text, use Extract Text from PDF on the original file first.
Which compression level should I use?
Start with Recommended. If the file is still too big, try High. If small text looks soft, go back to Low.
Why did my PDF get bigger?
The file was probably already efficient, made mostly of text and vector shapes. Turning those pages into images can weigh more. In that case, keep the original.
Can I compress a password-protected PDF?
Not if it needs a password to open. A file that opens freely but blocks printing or copying may fail too, so try Unlock PDF first.