PDF files get large fast — especially scanned documents, PDFs with embedded images, or multi-page reports exported from design tools. Email attachment limits, upload portals with size caps, and slow file transfers all become problems. Here are four free methods to compress a PDF, what each one actually does, and when to use which. Method 1: Browser-based compression (no upload) The PDF Compressor at Ultimate Tools compresses your PDF entirely in your browser. The file never leaves your device. How it works: Open the tool Drop your PDF file Choose compression level (light, medium, strong) Click Compress Download the compressed file The browser-side processing uses pdf-lib to re-encode the document. Image-heavy PDFs see the largest reductions (50–80% file size reduction is common). Text-only PDFs see smaller reductions since text data compresses well even in the original. When to use this: Any PDF with sensitive content (contracts, financial documents, medical records). The file never touches a server.…