What is PDF compression?
PDF compression reduces the file size of a document by optimizing its internal content — shrinking embedded images, removing redundant data, and stripping metadata that most readers don’t need. Your text, layout, and structure stay exactly the same. The result is a smaller file that opens, prints, and shares just like the original.
Most people compress PDFs to meet email attachment limits — Gmail caps at 25 MB, Outlook at 20 MB — or to upload documents to portals with a file size restriction. A 12 MB scanned contract, for example, can often shrink to under 2 MB with Balanced quality, with no visible difference on screen or in print.
Compression levels
Pick the level that fits your use case:
High Quality. Optimizes the file structure and removes hidden metadata while keeping the original image resolution. Best for presentations, branded reports, or any document where visual sharpness matters. File size reduction is typically 20–40%.
Balanced. The right choice for most files. Images are re-encoded at a resolution that looks identical on screen and in standard print, but takes up much less space. Most documents shrink by 50–70% with no noticeable quality loss.
Maximum Compression. Applies the most aggressive image optimization to produce the smallest possible file. Ideal for documents sent by email, uploaded to web forms, or archived digitally. Expect 70–85% size reduction. Fine detail in high-resolution photos may soften slightly.
How to use this compressor
Upload your PDF. Drop your file onto the upload area or click to browse. Files up to 100 MB are supported — scanned documents, reports, and image-heavy PDFs all work.
Choose a compression level. Pick High Quality to preserve sharpness, Balanced for most everyday documents, or Maximum Compression to get the smallest possible file size.
Download the result. The tool shows you the original size, compressed size, and percentage saved — then click Download to save the file to your device.
How PDF compression works
A PDF file can store far more data than is visible on the page. Scanned documents carry raw pixel data with no optimization. Embedded images are often saved at higher resolution than any screen or printer actually uses. Some PDFs embed the same font multiple times. Compression addresses all of this: images are resampled and re-encoded with more efficient formats, duplicate resources are merged, and unused metadata is stripped. Your text and document structure aren’t touched.
Is it safe to compress a PDF online?
Yes. Your file is sent over an encrypted HTTPS connection, compressed on the server, and returned to your browser. Files are processed instantly and never stored after your session ends — they aren’t retained, logged, or accessible to any third party. If you need to remove pages before compressing, use the Split PDF tool to extract only the pages you need first.