Compress PDF: A Practical Guide
Use Compress PDF to try to reduce a PDF’s file size. The current workflow rebuilds pages as optimized images, so stronger compression can reduce detail and remove selectable text or interactive behavior. Choose a setting based on readability, not just the smallest byte count.
How to Use Compress PDF
- Choose the PDF.
- Select an available compression level.
- Run compression.
- Compare original and output sizes, then inspect small text and diagrams in the downloaded copy.
Size Reduction Versus Fidelity
Image-heavy scans often have more room for reduction than already optimized files. A rebuilt document can sometimes be larger, especially when a small vector document is converted to page images.
Rasterization can affect searchability, accessibility, forms, links and signatures. Keep the original if those features matter. The output should be checked at the size where it will be read or printed.
Worked Example
For an application upload limit, start with a moderate setting and inspect a page containing the smallest text. Increase compression only if the result remains readable.
A smaller file with unreadable account numbers is not a successful submission. Confirm the portal’s actual size limit and document requirements.
Add searchable text after a scan workflow: use the OCR PDF.
Submit smaller sections where permitted: use the Split PDF.
Checks and Common Mistakes
- Do not assume every PDF becomes smaller.
- Check tiny text, barcodes and QR codes.
- Keep the source with selectable text when needed.
- Avoid repeated lossy recompression.
Frequently Asked Questions
Will the output still be searchable?
This image-rebuild workflow may flatten text. OCR can add recognized text later, but it requires separate checking.
Can compression restore a blurry scan?
No. It cannot recover detail absent from the source.
Which setting is best?
Use the least aggressive option that meets your size requirement while preserving the details relevant to the document.
Related Tools for the Next Step
- OCR PDF: Add searchable text after a scan workflow.
- Split PDF: Submit smaller sections where permitted.
- Remove PDF Pages: Remove genuinely unnecessary pages.
- PDF Info Checker: Inspect basic document information.
Reference
Further reading: PDF Association: PDF specification resources.