How to reduce PDF file size
A PDF that is too big for an email or an upload form is a common problem. The fix depends on why the file is big, so start with the cause.
Why a PDF gets big
Most of the weight in a PDF is pictures. A scanned document is one large photo per page, and a report with screenshots or photos carries every image at full size. Text on its own is tiny, so a file that is mostly text rarely needs shrinking.
Way 1: compress it in your browser
- Open the Filesmingo board and drop the PDF onto it.
- Select the card and open the Compress tab.
- Pick the image quality and the resolution. Lower values give a smaller file.
- Run it, check the new size, and download the result.
This works on your device, so the document is not uploaded. The tool redraws each page as a picture, which is why scans shrink the most.
Way 2: lower the resolution
For reading on a screen, around 100 to 150 dpi is usually enough. Higher resolution only matters if the file will be printed at a large size. Dropping from a high setting to a moderate one is the single biggest saving for scanned files.
Way 3: split it into parts
If a limit is about the size of one file, send the document in two or three parts. The Pages tab lets you keep a page range, for example 1-20, and create a new PDF from it. Text stays selectable because the pages are copied unchanged.
Way 4: shrink the pictures before they go into the PDF
If you build the PDF yourself from photos, compress or resize the images first, then turn them into a PDF. Starting with smaller pictures gives a smaller file than compressing afterwards.
What to check afterwards
Open the result and look at a few pages at the size you will actually use. Because compression turns pages into pictures, the text in the new file can no longer be selected or searched. If you need that, keep the original too.