How to Reduce PDF File Size (Make a PDF Smaller)

Large PDFs are slow to send and sometimes rejected by upload limits. The good news is that most PDFs can be made much smaller. To reduce PDF file size you generally compress it, and how much you can save depends on what is inside.

There are two levers. Lossless compression rewrites the file efficiently and keeps text and images pixel-perfect, which trims a modest amount. Lossy compression re-renders pages and downsamples images, which can cut a scanned or photo-heavy PDF by 70 to 90 percent at the cost of selectable text.

To reduce PDF size with PdfWill: open the Compress tool, upload your file, pick a level (light for text, stronger for scans), and download. Everything runs in your browser, so the file is never uploaded.

If only part of the document matters, split the PDF and keep the pages you need. And converting a color file to grayscale removes color data and shrinks it further.