How to reduce the size of a PDF
Big PDFs are almost always big because of images. Here’s how to shrink them without making them unreadable.
Compress a PDF online
- 1Open Compress PDF and choose your file.
- 2Pick a level: Low keeps the best quality, High makes the smallest file.
- 3Compress, compare the sizes shown, and download the result.
Why is my PDF so large?
- Scanned pages saved at a very high resolution
- Photos inserted at full camera size
- Fonts embedded many times over after repeated editing
- Several documents merged together
Choosing a compression level
Start with Medium. If the result still exceeds your limit, try High and zoom in to check the text is still readable. For documents that will be printed, stay on Low.
Other ways to make a PDF smaller
- Delete pages you don’t need with Delete PDF pages
- Split a long document into parts with Split PDF
- When scanning, choose 150–200 DPI and greyscale for text documents
Frequently asked questions
Does compression reduce quality?
Images may lose some sharpness at higher levels; text stays crisp because it isn’t turned into an image.