Is this PDF compressor free?

Yes, completely free. No account, no subscription, no watermarks, and no file size limits imposed by the tool itself.

Does the tool upload my PDF to a server?

No. Your PDF is processed entirely inside your browser using pdf.js. It never leaves your device and is never sent to any server, making it safe for confidential or sensitive documents.

Why did my PDF size barely change after compression?

This tool works by rasterizing pages, so it is most effective on scan-heavy or image-heavy PDFs. If your PDF already contains mostly vector text and graphics (like an exported Word document), the rasterization may not reduce the size significantly — and could even make it larger. For text-only PDFs, try a dedicated tool that optimizes fonts and vectors instead.

Will the compressed PDF still have selectable text?

No. Because this tool rasterizes pages into images, the output PDF is image-based. Text will not be selectable, searchable, or copy-pasteable. If you need to preserve text selectability, this compression method is not the right fit.

Does it work on mobile phones and tablets?

Yes. The tool runs in any modern browser, including mobile Safari and Chrome on iOS and Android. Processing time may be longer on slower devices since all work is done on your device's CPU.

🗜️ Compress PDF — Reduce File Size Instantly, No Upload

Reduce your PDF file size instantly — for free, with complete privacy. This tool rasterizes PDF pages at your chosen DPI (light, medium, or strong) entirely inside your browser using pdf.js. Your file is never uploaded to any server; everything happens locally on your device. Looking for a free iLovePDF alternative? Toolio’s version is completely free and needs no sign-up.

PDF compression reduces a file's size by optimizing its images and structure while keeping the document readable.

Choose a PDF

Compression

Runs in your browser — your file is never uploaded. Best for scan/image-heavy PDFs.

Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.

About

PDF Compress works by rendering each page of your PDF to an image at a reduced DPI using pdf.js, then repacking those images into a new, smaller PDF. Light mode uses a higher DPI to preserve readability; strong mode uses a lower DPI for maximum size reduction. This approach is most effective on scan-heavy or image-heavy PDFs. Because text is converted to images, the resulting PDF will not have selectable or searchable text — keep this in mind if you need copy-paste functionality. All processing happens 100% client-side; your PDF never leaves your browser, making it safe for confidential documents.

How to use

Click "Choose PDF" and select the PDF file you want to compress from your device.
Choose a compression level: Light (high DPI, best quality), Medium (balanced), or Strong (lowest DPI, smallest file).
Click "Compress PDF" and wait while your browser processes each page.
Download your compressed PDF. The new file size is shown so you can compare before and after.

FAQ

Is this PDF compressor free?: Yes, completely free. No account, no subscription, no watermarks, and no file size limits imposed by the tool itself.
Does the tool upload my PDF to a server?: No. Your PDF is processed entirely inside your browser using pdf.js. It never leaves your device and is never sent to any server, making it safe for confidential or sensitive documents.
Why did my PDF size barely change after compression?: This tool works by rasterizing pages, so it is most effective on scan-heavy or image-heavy PDFs. If your PDF already contains mostly vector text and graphics (like an exported Word document), the rasterization may not reduce the size significantly — and could even make it larger. For text-only PDFs, try a dedicated tool that optimizes fonts and vectors instead.
Will the compressed PDF still have selectable text?: No. Because this tool rasterizes pages into images, the output PDF is image-based. Text will not be selectable, searchable, or copy-pasteable. If you need to preserve text selectability, this compression method is not the right fit.
Does it work on mobile phones and tablets?: Yes. The tool runs in any modern browser, including mobile Safari and Chrome on iOS and Android. Processing time may be longer on slower devices since all work is done on your device's CPU.

Read the guide