Compress PDF

Reduce PDF file size while maintaining quality. Perfect for email attachments and uploads.

Shrink PDFs to a fraction of their size with no visible quality loss.

or drop the pdf here

100% Private

Instant Processing

Browser-Based

Compress PDF Online with PDFSub

Features

Significant size reduction

Maintains readability

Removes unused metadata

Fast compression

No visible quality loss

Ideal for email attachments

Files encrypted during transfer, auto-deleted after processing

How It Looks

Original Size

Compressed

How It Works

Upload your PDF file

Our tool analyzes and optimizes

Review the size reduction

Download your compressed PDF

Common Use Cases

Reducing email attachment size

Meeting upload size limits

Saving storage space

Faster document sharing

Frequently Asked Questions

How much can I reduce my PDF file size?

Compression results vary depending on the content. PDFs with high-resolution images typically see the greatest reduction, often 50-80% smaller.

Will compression affect text quality?

No, text remains sharp and clear. Our compression primarily optimizes images and removes unnecessary metadata while preserving readability.

Is there a file size limit for compression?

Yes - uploads are capped at 100 MB per file. For larger PDFs, split them first with the Split PDF tool, compress each part, then merge the compressed parts back together.

Is my file processed securely?

Your files are processed securely by the PDFSub Engine - an isolated server with no internet access. Files are encrypted during transfer and auto-deleted after processing.