Compare the editor's tracked corrections with the latest pages and mark any edits that haven't been applied; add comme…
Open the PDF file you want to clean in Adobe Acrobat.
Select Tools in the upper left, then choose Optimize PDF from the tools list.
In the secondary toolbar, click More Options (three dots), then select PDF Optimizer.
In the PDF Optimizer dialog, click Audit space usage if you want to see what elements are taking up space.
Best practiceAuditing space usage can help you identify which hidden elements or metadata are consuming the most space before removal.
Click Discard Objects and check options such as Discard hidden layer content and flatten visible layers, Discard all alternate images, and any other options relevant to hidden content.
Click Discard User Data and check options like Remove metadata, Remove hidden layer content, Remove embedded search index, Remove document information and metadata, and Remove file attachments.
CautionRemoving metadata and attachments is irreversible once saved; ensure you have a backup if you may need this information.
Review all selected options to confirm you are removing all desired hidden data, metadata, and attachments.
Click OK to apply the changes.
Save the optimized PDF with a new name to preserve the original file if needed.
Best practiceBest practice is to save a copy after optimization to avoid accidental data loss.
You can preview which elements will be removed by using the Audit Space Usage feature before finalizing the optimization.
This runs in the Acrobat app - there is no separate API for this task.
Downsampling changes images by reducing their detail, making them smaller. For example, a 300 dpi image might become 150 dpi. Unembedding fonts removes the actual font data from the PDF. If the reader's computer has the font, it will use that. Both actions help reduce the PDF's total file size, but they affect different parts of the document.
You should use RGB colors for PDFs that will be viewed on a screen because screens display colors using RGB (Red, Green, Blue). CMYK (Cyan, Magenta, Yellow, Black) is for printing. Using RGB ensures your colors look correct and vibrant on monitors and devices, preventing dull or inaccurate color display.
If your PDF has scanned pages, you should use the 'Optimize Scanned Pages' option in Acrobat. This feature is made specifically for scans. It helps to clean up and reduce the size of scanned documents more effectively than general optimization settings.
Invalid bookmarks and links are navigation aids in a PDF that no longer point to a correct place within the document or to a valid external website. They might be left over from editing or changes. PDF Optimizer can remove these broken elements. This cleans up the file and can make it slightly smaller, improving the user experience by removing non-functional parts.