How to use Compress PDF
Choose a PDF up to 25 MB and 200 pages. The tool re-saves it in your browser and shows both file sizes, then you download the new copy if it is smaller.
What this compression does
Many PDFs are saved with a loose internal structure, especially files exported from older software or edited several times. Re-saving them with object streams removes that overhead, which can shrink text-heavy documents noticeably. Your pages, fonts and images stay exactly as they were, so nothing becomes blurry.
When a file will not shrink much
If most of the size comes from photos or scanned pages, structural compression cannot help a lot, because this tool does not recompress images. In that case, export the document again with a lower image quality from the app that created it, or reduce the scan resolution. A small file can even grow slightly, and the tool tells you when that happens.
How to reduce PDF size further
This tool is a lossless PDF compressor: it repacks the file without touching text or images, so quality stays high. That works best on text-heavy documents and files that were edited many times. For an image-heavy PDF, such as a scanned contract or a brochure full of photos, the big savings come from lowering the image resolution. Export it again from the original app at 150 dpi, or print it to PDF with a smaller image setting, then run it through here.
Size limits you are likely to meet
Email services often cap attachments at around 20 to 25 MB, and many government and job portals accept only 2 to 10 MB per upload. If a large PDF file is still over the limit after compressing, split it into parts with the split PDF tool and send them separately.
How it works
PDF reserialization with object streams
Examples
- Worked example
The tool attempts structural optimization and shows whether the output became smaller.
Limitations and assumptions
This is not image recompression. Some PDFs may not shrink and can become slightly larger.
Frequently asked questions
Is my PDF uploaded?
No. The file is read and rebuilt in your browser and never leaves your device.
Will the quality get worse?
No. Text, fonts and images are kept as they are. Only the way the file is packed changes.
Why did my file not get smaller?
It was probably already compact, or most of its size is images. Try exporting it again with lower image quality from the original app.
Is there a size limit?
Yes, 25 MB and 200 pages per file, so large documents stay quick to process in the browser.