Compress PDF
Compress PDF Online – Reduce PDF File Size for Free. No watermark added by QuickConvertOnline. Free, no account needed.
About Compress PDF
Compress PDF reduces the size of a PDF in one of two ways. Lossless mode rewrites the file with QPDF, packing objects into compressed streams and recompressing data at the highest level, while keeping text, links and forms intact. Smaller scans mode re-renders each page as a JPG at the resolution and quality you choose.
Lossless suits documents created by software, while Smaller scans is meant for scanned and photo-heavy files that must fit an email or upload limit. If the result would not be smaller, the tool keeps your original and tells you. Everything runs in your browser, so the file is never uploaded.
How to use Compress PDF
- Drop one or more PDFs onto the page or select Choose PDF.
- Choose a Compression mode: Lossless (preserve text and forms) or Smaller scans (flatten pages).
- For Smaller scans, pick a resolution (DPI) and quality; lower values give smaller files.
- Select Apply, compare the new size with the original and select Download.
Features
- Lossless mode with object streams and maximum Flate recompression; the content looks exactly the same.
- Smaller scans mode that saves pages as JPG images at 72 to 300 DPI and 20% to 100% quality.
- Keeps each page's original dimensions in both modes.
- Never returns a bigger file: if compression does not help, the original is kept.
- Shows the result size so you can compare it with the original.
- Compresses up to 12 PDFs in one run.
Common uses
- Getting a PDF under an email attachment limit.
- Meeting the upload size limit of a job, visa or university portal.
- Shrinking scanned contracts and receipts before archiving them.
- Making a document quicker to download on mobile data.
Tips
- Start with Lossless. If the file is a scan and still too large, try Smaller scans at 144 DPI and 70% quality.
- Keep your original file: flattening with Smaller scans cannot be undone.
Frequently asked questions
Will compressing a PDF reduce quality?
Lossless mode does not change how the document looks; it only stores the same data more efficiently. Smaller scans mode does affect quality: pages become JPG images, so fine detail can soften at lower DPI or quality, and text is no longer selectable.
Why didn't my PDF get much smaller?
Lossless mode repacks the file's structure and data but does not downsample images. PDFs already optimized by the app that made them, or built mostly from JPG images, may shrink very little. For scans and photo-heavy files, Smaller scans usually makes a bigger difference.
What does This PDF is already optimized mean?
The compressed version came out the same size or larger than your file, so the tool keeps the original instead of giving you something worse. Try Smaller scans if the PDF is mostly images.
Does compression remove links and form fields?
Lossless mode keeps them. Smaller scans flattens every page into an image, which removes searchable text, links, form fields and other interactive elements. The tool shows a warning whenever this mode is selected.
Is the password kept after compressing a protected PDF?
No. You enter the password to open the file, and the compressed copy is saved without encryption. Run the result through Protect PDF if it needs a password again.
Is my input uploaded?
Tools run in your browser. Files, text and results are not uploaded to our servers and are cleared when you leave the tool.
Your privacy comes first
Tools run in your browser. Files, text and results are not uploaded to our servers and are cleared when you leave the tool.