Why PDFs become too large
PDF size usually increases because of scanned pages, large embedded images, unnecessary metadata, or high-resolution exports.
Text-based PDFs are often already efficient, while image-heavy files usually have the biggest reduction potential.
How compression works
Compression reduces the file by optimizing images, fonts, and internal PDF data. The strongest compression creates smaller files, but it can also reduce sharpness.
Best practical approach
- Use medium compression first
- Check readability after compression
- Use stronger compression only when upload limits are strict
- Keep original files saved separately