When to use strict mode first
Strict mode is a good first pass when preserving visible appearance matters more than achieving the smallest possible file size. It focuses on safer cleanup and optimization steps.
Free PDF Compressor
Reduce PDF size online with display-preserving defaults first, then move to balanced or stronger compression when you need more savings.
Strict, balanced, and maximum compression modes.Optional image recompression and downsampling controls.Optimize up to 4 PDF files in one job.
When to use stronger compression
Balanced and maximum modes are useful when you need stronger file-size reduction and are willing to trade off more aggressive image handling to get it.