PDF Compressor

How to Compress a PDF Online

Compressing a PDF file is simple with our free tool. Just upload your PDF, select your preferred compression level, and download the reduced file. Your data stays private — all processing happens in your browser with no uploads to our servers.

Compression Levels Explained

We offer three compression levels to suit different needs. The Low setting provides minimal reduction while keeping image quality high — ideal for documents with photos or detailed graphics. The Medium setting (recommended for most users) balances file size reduction with acceptable quality, typically reducing PDF size by 30-50%. The High setting applies aggressive compression for the smallest possible file, best for plain text documents or when file size is critical.

How PDF Compression Works

Our PDF compressor works entirely in your browser using advanced compression algorithms. When you upload a PDF, we render each page at the selected resolution and re-encode the images with the corresponding quality setting. This reduces embedded image file sizes without removing content. The entire process is instant and your PDF file never leaves your device.

When Should You Use Each Level?

Use the Low compression level for design documents, presentations, or PDFs containing important visuals where quality is paramount. The Medium level works well for business documents, contracts, and general office files. Choose High compression for plain text documents, forms, or when you need to minimize file size for email attachments or storage.

Frequently Asked Questions

Is my PDF kept private?

Absolutely. All compression happens 100% in your web browser. Your PDF file is processed locally and never sent to any server. Once you close your browser or refresh the page, the file is completely gone from memory.

What's the maximum PDF file size I can compress?

The maximum file size depends on your browser and available RAM, typically 500MB-1GB. For best performance, we recommend files under 100MB. Very large files may take longer to process.

Will compression reduce quality noticeably?

The Medium and Low settings maintain good quality for most documents. High compression is more noticeable and best used for text-only PDFs. Test with a small file first to see results that match your needs.

Can I compress PDF files with scanned images?

Yes! Our tool works with any PDF, including scanned documents. For scanned PDFs, compression can be very effective since they contain embedded images. Medium or High compression usually produces good results.

What if I accidentally select the wrong compression level?

No problem! Simply click "Compress Another PDF" to reset the tool and try again with a different setting. You can experiment with different levels to find the perfect balance for your needs.

Does compression affect searchable text in PDFs?

Compression preserves the text layer in PDFs, so searchable text remains searchable after compression. Only the visual quality of images is affected by the compression level.