Why are some PDFs so big?
A PDF made from phone photos or a scanner stores every page as a high-resolution image, often several megabytes per page. PDFs made from Word or Google Docs are mostly text and are usually small already. Knowing which kind you have tells you how much you can save.
Which compression level should you use?
| Level | How it works | Best for |
|---|---|---|
| Light | Re-saves the PDF more efficiently; text stays selectable | Text documents, when you must keep copyable text |
| Recommended | Redraws each page as a 150 DPI image | Scans, photographed assignments, certificates |
| Strong | Redraws each page as a 100 DPI image with stronger compression | Portals with strict limits like 1 MB |
In our tests, a 7 MB scanned PDF came down to about 0.8 MB on Recommended and about 0.25 MB on Strong. Results depend on the document.
Common size limits
Many university portals, job sites and government services in Pakistan and India ask for files between 200 KB and 5 MB. Start with Recommended; if the file is still too big, try Strong. For very strict limits, split the document with Split PDF and compress each part.
Things to know
- Recommended and Strong turn pages into images, so text can't be selected or searched afterwards. Keep your original if you need that.
- If the result isn't smaller, the PDF was already well optimised. Keep the original.
- Password-protected PDFs can't be opened in the browser.
Read our full guide on how to reduce PDF file size for online forms.