Are my PDF files uploaded to a server?

No. Compression happens entirely in your browser using pdf-lib and the HTML5 Canvas API. Your files never leave your device.

How much can I reduce the file size?

Results vary by PDF content. Documents with many high-resolution images typically shrink by 30-70%. Text-only PDFs may see little reduction because there are no images to recompress.

What is the difference between the quality levels?

Low quality applies the most aggressive JPEG compression and produces the smallest file. Maximum quality applies minimal compression to preserve image fidelity with a modest size reduction.

Will compression affect text or vector graphics?

No. Only raster images embedded in the PDF are recompressed. Text, fonts, vector shapes, and document structure are preserved exactly.

PDF Compressor

Name: PDF Compressor
Availability: InStock
Author: Nham Vu

Drop a PDF, pick a compression quality, and download a smaller file — no upload required.

Compression Settings

Click or drag a PDF here

One file at a time

Compression Quality Medium

Low Medium High Maximum

Lower quality = smaller file. Higher quality = better image fidelity.

Files never leave your device.

Result

No file selected

Upload a PDF to see compression results

Summary

Drop a PDF, pick a compression quality, and download a smaller file — no upload required.

How it works

Drag your PDF onto the upload zone or click to select a file.
Choose a compression quality: Low, Medium, High, or Maximum.
Click "Compress PDF" and wait for processing to finish.
Review the size comparison, then click Download or Preview.

Use cases

Shrinking large PDF reports before emailing them to clients.
Reducing scanned document size for cloud storage.
Making PDF presentations small enough to attach to a form submission.

Frequently Asked Questions

Last updated: 2026-06-25 · Reviewed by Nham Vu