Reduce PDF file size by rasterizing pages as compressed images. Works best for image-heavy and scanned PDFs.
Choose a PDF file to compress.
Note: Compression works best on image-heavy and scanned PDFs. Text-based PDFs may not shrink significantly, and text will be rasterized as images (no longer selectable or searchable).
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What is the Compress PDF?
A PDF compressor reduces file size by converting each page into a rasterized image (JPEG) at a lower resolution and quality setting. The tool renders each PDF page to a canvas using pdf-lib and pdfjs, exports it as a JPEG with your chosen quality level, and embeds those JPEGs into a new PDF. This works best for image-heavy and scanned PDFs; text-based PDFs may not compress as much, and their text becomes non-selectable.
How it works
Upload your PDF and select a quality preset (High, Medium, or Low). The tool loads the PDF and renders each page to a canvas at the selected scale (1.5× for High, 1.2× for Medium, 1.0× for Low). Each page is exported to JPEG at the corresponding quality (0.8, 0.65, or 0.5 on a 0–1 scale). These JPEGs are then embedded into a new PDF at the original page dimensions. You see the before and after file sizes, plus the compression percentage.
How to use the Compress PDF
Upload a PDF file (drag-and-drop or browse)
Choose a quality preset: High (best quality, moderate compression), Medium (balanced), or Low (maximum compression)
Click 'Download Compressed PDF' to process the file
The tool renders all pages to JPEG, embeds them in a new PDF, and downloads the result
Compare the original and compressed file sizes in the stats section
Benefits
Reduce file size dramatically for scanned documents and image-heavy PDFs (often 50–80% smaller)
Choose your compression trade-off: High preserves detail, Medium balances size and quality, Low maximizes compression
No upload or account required—everything happens in your browser
Instantly compare before and after file sizes to decide if the quality is acceptable
Perfect for email attachments, cloud storage limits, and sharing large documents
Works on any PDF, including multi-page documents with hundreds of pages
Tips & common mistakes
Common mistakes
Compressing a text-based PDF expecting it to shrink significantly; text PDFs may not compress much because text is already efficient
Using Low quality when detail matters; compressed text and fine lines become blurry and hard to read
Forgetting that compressed PDFs lose selectability and searchability; text becomes part of the image, not extractable
Compressing already-compressed PDFs (like photos or pre-compressed scans); you may not gain much reduction
Expecting lossless compression; JPEG compression is lossy, so quality is permanently reduced after download
Tips
For legal or important documents, use High or Medium quality to preserve readability. Reserve Low quality for casual sharing or archival.
Test compression on a single page first if unsure: split the PDF, compress one page, and review the quality before processing the entire document.
If your PDF is mostly text, consider extracting text and recreating the document in a word processor instead of compressing; you'll get much better results.
Scanned documents compress best because they're already images; pure text PDFs may see little reduction—choose Medium or High quality for text.
Use this tool to compress before uploading to cloud storage, email, or document sharing services to save bandwidth and storage.
Remember: compression is lossy. Once downloaded, the original quality is lost. Keep the original if you may need it later.
Frequently asked questions
Will compressed text be selectable and searchable?
No. When pages are rasterized to JPEG and embedded, the text becomes part of the image layer. You cannot copy, search, or select text in the compressed PDF. Use a text-based compressor (not this one) if you need to preserve selectability.
How much will my PDF shrink?
It depends on the original content. Image-heavy and scanned PDFs often shrink 50–80%. Text-based PDFs may shrink only 10–30% because text is already compact. Compression percentage is shown after you download.
Should I use High, Medium, or Low quality?
High: best for documents where clarity matters (contracts, receipts, ID scans). Medium: good balance for most uses (reports, articles, general sharing). Low: maximum shrinkage for casual sharing or archival where quality is less critical.
Can I compress a password-protected PDF?
No. The tool cannot load encrypted PDFs. You must remove the password protection first, then compress.
What file sizes can I compress?
Most browsers handle files up to 100–200 MB. Very large files (500+ MB) may be slow or timeout. For huge PDFs, split them first, then compress each section.
Is compression permanent?
Yes. Compression is lossy; once you download the compressed PDF, the original quality is gone. Always keep a backup of the original if you may need it later.
Does the tool upload my PDF to a server?
No. All compression happens entirely in your browser. Your PDF never leaves your device.
Why does my text-based PDF not shrink much?
Text in PDFs is already compact. Rasterizing it to JPEG adds overhead and may not reduce size. Compression works best on image-heavy and scanned documents where images are the bulk of the file size.