Free PDF tool
Compress PDF Online for Free
Compare high, medium, and low PDF compression profiles. Check actual output size and readability, with clear guidance on estimates and quality trade-offs.
Use Compress PDF free →No signup required · Everyday files are processed in your browserSimple and focused
Compress PDF without installing software
Make large PDFs easier to email, upload, and archive. Choose stronger compression for a smaller file or lighter compression when preserving visual quality matters most.
Compression is most useful when images or scans dominate a PDF. A short document containing efficiently stored text may already be smaller than a re-rendered version. A small saving is not necessarily an error.
Before you start
Keep an untouched master. Decide whether the recipient needs selectable text or just a readable visual copy. If the destination has an upload limit, check its exact limit and units before choosing a quality setting.
How it works
Finish in three steps
Choose the PDF you want to reduce.
Select high, medium, or low compression.
Review the result and download the smaller PDF.
Built for everyday PDFs
What this tool gives you
- ✓Three compression profiles
- ✓Previews estimated from sample pages
- ✓Avoids a recompressed file larger than the original
Practical example
Make an email copy without losing fine print
- Start with Low and inspect the smallest text, stamps, and diagrams in the downloaded result at 100% and a higher zoom.
- Try Medium on the original if Low is still too large. Use High only if its result remains legible for your purpose.
- Compare the actual downloaded sizes, then keep the clearest version that meets the recipient's limit.
The output may be smaller or the original may be retained. Different settings are not guaranteed to produce three different sizes for every document.
Capabilities and limits
- Image-based compression can turn pages into JPEG images. Text selection, links, form interactions, and some fine detail can be lost.
- Before processing, estimates sample the first and last pages. A photograph-heavy middle section can make the final size differ substantially. The completed download size is the authoritative result.
- The compressor compares candidates with the source and avoids returning a larger recompressed file. There is no guaranteed reduction percentage or exact target-size control.
When the result is unexpected
The estimate does not match the download
An estimate is a projection from sample pages, not a promise. Wait for the completed output and compare its actual size.
Small labels look soft
Return to the original and use a lighter level. Do not repeatedly compress an already compressed copy.
Check the downloaded file
Inspect the most detailed page, not only the cover. Try searching and selecting text if those abilities matter. If the quality or features are unacceptable, share the original or split the document instead.
Questions
Compress PDF FAQ
Which compression level makes the smallest PDF?
High compression is designed for the smallest result. Medium balances clarity and size, while low preserves the most visual detail.
Why does PDF quality change?
Strong compression can rasterize pages and reduce image detail. Use medium or low when fine print and images need greater clarity.
Ready to work on your PDF?
Open Compress PDF, choose your file, and download the result.
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