PDF file size is often driven by embedded images, fonts, scans, and duplicated resources. A PDF with high-resolution photographs may be much larger than a text-only document.
Try the browser optimizer
Open Compress PDF and select a document. The current tool re-saves the PDF with object streams, which can help with some files but does not recompress embedded images. The result may not always be smaller.
For image-heavy PDFs
For a substantial reduction, the source images may need to be resized or recompressed before the PDF is created. Be aware that lossy image compression can reduce visual quality.
Compare before sharing
Check the output file size and inspect fine text, charts, and images at normal viewing size. Keep the original when quality matters.
Editorial note: Tool behavior may change as the site is updated. Always follow the limitation notice shown on each tool page.