PDF Compressor — Reduce PDF File Size Free Online
Reduce PDF file size instantly
Compress PDF files without losing quality. Remove unnecessary metadata and optimize content streams to shrink file size.
About PDF Compressor
PDF compression reduces the file size of a PDF document by removing redundant data, compressing internal object streams, and stripping unnecessary metadata without altering the visible content. Smaller PDFs are easier to email, faster to upload to web forms, and consume less storage.
PDF files accumulate bloat over time — especially when created by desktop applications that embed application metadata, edit history, thumbnail previews, and uncompressed cross-reference tables. By enabling object stream compression and removing this overhead, the file size can often be reduced by 10–40% with no perceptible change to the document's appearance.
Common use cases include reducing the size of scanned documents before email submission, compressing PDFs to meet upload limits on government or institutional portals, reducing storage consumption of large PDF archives, and optimising PDFs before embedding them on websites.
This tool uses a dual-engine compression pipeline (Ghostscript plus an image re-encoding engine) on our servers to deliver real, reliable size reductions across every type of PDF — including scanned documents that simpler compressors can't shrink. Your file is processed in memory and permanently deleted immediately after your result is returned — never stored, viewed, or shared.
Frequently Asked Questions
How does PDF compression work?
This tool removes unnecessary metadata, comments, and unused objects, and enables cross-reference stream compression. It does not reduce image resolution or re-encode embedded images.
How much can I expect the file size to reduce?
Results vary depending on how optimised the original PDF already is. Documents with extensive metadata, redundant objects, or uncompressed cross-reference tables may shrink by 10–40%. Highly optimised PDFs may see minimal reduction.
Will the compressed PDF look different?
No. The visual content — text, images, and layout — remains identical. Only invisible overhead data is removed.
Are my files safe when I use this tool?
Yes. Your PDF is compressed using a professional dual-engine pipeline (Ghostscript + pdf-lib) on our servers — handled in memory and permanently deleted immediately after your result is returned.