Prepare the proposals bundle for review: compress the large figures and data appendices, combine them with the proposa…
Open your PDF file in Adobe Acrobat.
Go to the File menu and select Save As Other.
Choose Reduced Size PDF from the submenu.
Select the desired compatibility option in the dialog that appears.
CautionChoosing a lower compatibility may prevent older PDF viewers from opening the file.
Click OK to proceed.
Enter a new file name and location if prompted, then click Save.
Best practiceFor best results, always save the reduced file as a new copy to preserve your original PDF.
You can quickly reduce the file size of your PDF using the 'Save as Other' option in the File menu.
This runs in the Acrobat app - there is no separate API for this task.
Reducing PDF file size often works by lowering the quality of images inside the document. For example, it might change images from 300 DPI (good for printing) to 72-100 DPI (good for viewing on a screen). This saves space but can make images look blurry or pixelated if you try to print them or view them very large. Text is usually not affected, only pictures.
If your PDF is already small, trying to reduce its size again is not usually helpful. Each time you compress a file, especially one with images, the quality can get a little worse. It's best to compress only when needed and always start from the original file to keep the best quality.
| Compression Level | Effect on File Size | Effect on Image Quality | Best Use Case |
|---|---|---|---|
| Low (High Quality) | Moderate reduction (10-30%) | Minimal or no change | Emailing, general sharing, when image quality is important |
| Medium | Good reduction (30-60%) | Some visible change, images become less sharp | Web upload, situations where file size is critical but some quality can be lost |
| High | Significant reduction (60% or more) | Noticeable loss of detail, images may look blurry | Very small files needed, on-screen viewing only, when file size is the top priority |
It is important to compress a PDF from its original file because each time you compress a copy, the quality of the images can get worse. If you compress a file that has already been compressed, you are degrading the quality further from an already lower-quality version. Starting with the original ensures you begin with the best possible image quality before any reduction happens.