Compress PDF

Frequently asked questions

• Can I compress multiple PDFs at once?

  Currently, Lumin compresses one file at a time. This ensures each document is processed efficiently and retains the best possible quality. You can easily compress multiple PDFs by uploading them one after another in the same session.

• Is it free to compress PDFs?

  Yes, Lumin offers free compression for basic use with generous daily limits. Create a free account to unlock more compression tasks and access advanced tools.
  
  Note: Users on the Free and Pro plans can utilize the Standard compression level for files that are 20 MB or smaller. Users on Business or Enterprise plans can compress files that exceed 20 MB.

• Will compressing a PDF affect its quality?

  The impact on quality depends on the compression level you choose. High compression keeps your file sharp while slightly reducing size, while medium and low levels prioritize smaller file sizes with minimal visible changes. 
  
  Use the preview feature to find the right balance for your needs.

• How do I compress a secured or locked PDF?

  Simply enter the document password when prompted to unlock editing. Lumin preserves all security settings during compression, ensuring your file remains protected. 
  
  The compressed version keeps your original passwords and permissions intact.

• Can I compress image-heavy or scanned PDFs?

  Absolutely. Lumin is designed to handle image-rich and scanned documents efficiently. It optimizes both text and image data to significantly reduce size while maintaining clear, readable results, making it ideal for photo-heavy or digitized files.

• Does compression affect printing or sharing?

  No, compressed PDFs remain fully functional. The file format and layout stay the same, only the size changes. Smaller files actually make sharing and uploading faster and easier.

• Can I reverse compression or restore the original file?

  Compression cannot be reversed, so it’s best to keep a copy of your original file before compressing. Lumin automatically saves the compressed version as a new file, leaving your original untouched.

• How long does it take to compress a PDF?

  Most PDFs compress in just a few seconds. Processing time varies by file size and compression level, but even large documents usually finish within 30 seconds. Smaller files typically take less than 5 seconds.

• Is it safe to compress PDFs online?

  Yes. Lumin uses bank-level 256-bit AES encryption and secure servers to protect your data. All files are transferred through encrypted connections, ensuring total privacy and security.