PDF Compressor
Reduce PDF file size while maintaining quality
Accepted upload: .pdf · max 20.00 MB per file · one PDF at a time. All processing happens in your browser. Your files never leave your device.
Drop a PDF here, or click Choose PDF
Shrink image-heavy PDFs locally. Text stays selectable.
Compression results
Empty — compress a PDF to see sizes here
No file loaded yet.
Frequently asked questions
Common questions about the PDF Compressor.
How does PDF Compressor work?
ToolsArk copies your pages in the browser with pdf-lib, then recompresses supported images (JPEG and uncompressed RGB or grayscale). Text stays as text — pages are never flattened into pictures. Choose Low, Balanced, or High compression.
Do my PDFs leave my device?
No. All processing happens in your browser. Your files never leave your device. ToolsArk does not upload PDFs to a server or call an external compression API.
Will every PDF get smaller?
No. Text-only or already compact files often cannot shrink in the browser without flattening pages, which would hurt readability. If nothing meaningful is saved, ToolsArk keeps the original bytes and tells you instead of pretending compression occurred.
What is the difference between Low, Balanced, and High?
Low keeps maximum image quality with a small size drop. Balanced is the default and aims for a noticeable reduction with little visible change. High shrinks more and may make photos look softer; you are warned before using it.
Why did a file fail to load or compress?
The file may not be a PDF, may be empty, larger than the size limit, password-protected, or corrupted. Encrypted PDFs cannot be compressed in the browser. Use a valid, unencrypted PDF.
Tags
Continue with these utilities
People frequently use these utilities together.