Shrink your PDF file size while keeping great visual quality. Free, fast and secure
How to compress a PDF
Upload the PDF you want to shrink (up to 500 MB).
Seleniun optimizes images and internal structure to reduce size.
Download the compressed file and check the reduction achieved.
Why compress a PDF with Seleniun
Smaller files are easier to email or upload where size limits apply.
Compression aims to keep visual quality close to the original.
The exact reduction depends on the content of each PDF (text-heavy files compress less than image-heavy ones).
Common uses
Attaching a large PDF to an email with a size limit.
Reducing storage space for scanned documents or reports.
Speeding up uploads to a website or online form.
Frequently asked questions about compressing PDFs
Will I lose quality when compressing my PDF?
Compression is optimized to keep visual quality as high as possible, but some quality loss can occur on image-heavy files; it is not guaranteed to be lossless in every case.
How much smaller will my file get?
It depends on the PDF's content — files with large images usually shrink more than text-only files. The exact percentage is shown after compression.
What is the maximum file size?
Compress PDF currently supports files up to 500 MB.
Is my file stored after compression?
No. Files are removed automatically after the compressed version is generated.
Need more tools?
Explore our other document conversion and optimization utilities.