PDF Compressor

What is PDF Compressor?

Shrink PDF file size with structural compression — object-stream packing and unused-resource cleanup. Typical savings are 10-30% on text-heavy PDFs; image-heavy scans see smaller gains because the embedded images themselves are not recompressed (a feature planned for a future server-side pass). Use when you need to fit a PDF under an email or upload size limit without switching to a different file format.

How do I use PDF Compressor?

1. Drop a PDF onto the upload zone.
2. Click Compress.
3. The panel shows the size saving percentage.
4. Click Download to save the compressed PDF.

PDF Compressor by the numbers

Engine

pdf-lib, in-browser

Max file size

100 MB

Typical savings

10–70%

Processing time

~1–8 seconds / file

Privacy

File never leaves browser

Common use cases for PDF Compressor

• Shrinking a scanned contract below a 5 MB email attachment limit.
• Preparing a portfolio PDF that needs to load quickly on a slow mobile connection.
• Cutting down a 40 MB e-book to fit a university LMS upload quota.
• Compressing a report with dozens of embedded photos before sharing in Slack.
• Batch-optimising invoices before archiving to a customer drive.

Common pitfalls and how to avoid them

• Text-only PDFs barely shrink — Most text PDFs are already near-optimal. Try removing unused fonts and images if you need further savings — or use a different source generator.
• Scanned PDFs stay large — Scanned pages are really images. For scans, rasterise to JPG with PDF-to-JPG, compress with Image Compressor, then rebuild with Image-to-PDF.
• Compressed text looks fuzzy — You compressed the embedded images too aggressively. Retry at a higher quality setting (75–85%) and re-download.

When should I use PDF Compressor?

PDF Compressor is best for text-heavy PDFs. For image-heavy scans, compressing the images first with Image Compressor, then rebuilding with Image to PDF, often saves more than running the scan through PDF Compressor directly.