Compress PDF & shrink file size

Pick your trade-off: free Basic compression rewrites streams losslessly, while Pro Moderate and Strong tiers downscale images and DPI for dramatically smaller files — with anti-bloat protection either way.

How to Compress PDF & shrink file size

1. Step 1. Upload your PDF.
2. Step 2. Pick a tier: Basic (free), or Pro Moderate/Strong for image + DPI downscaling.
3. Step 3. Click Execute — the anti-bloat guard keeps the original if a tier would not help.
4. Step 4. Compare the before/after size in the result panel and download.

Frequently asked questions

How much smaller will my PDF get?

It depends on the file: documents with duplicate resources or inefficient streams often shrink 20–60%. Already-optimized files may barely change — the estimator gives a rough guide per tier.

What is the difference between Basic, Moderate, and Strong?

Basic (free) rewrites content streams losslessly. Moderate and Strong (Pro) additionally re-encode images at lower quality and downscale DPI to ~150/~96 — much smaller files with lower image fidelity.

Is compression lossless?

Basic is lossless. Moderate and Strong re-encode images (visually lossy) to reach much smaller sizes.

Why didn’t my file get smaller?

If the PDF was already optimized, there is little to gain. Anti-bloat protection keeps your original file whenever a compression pass would not shrink it.