Compress PDF
Reduce your PDF file size for free — right in your browser. Choose from lossless cleanup, optimised re-save, or aggressive JPEG re-render. No uploads, no sign-up.
How it works
- 1Upload your PDF
Drag and drop a PDF file or click the upload area to browse. Your file stays on your device.
- 2Choose compression level
Pick Low for lossless, Medium for a balanced reduction, or High for maximum file-size savings.
- 3Download the result
Click Compress PDF, review the savings, and download your smaller file instantly.
Why Compress PDFs and When Does It Matter?
PDF files are the universal format for sharing documents, but they can grow surprisingly large. Scanned contracts, image-heavy reports, and design portfolios often balloon to tens of megabytes, making them slow to email, painful to upload to web forms, and heavy on mobile data. A good PDF compressor solves these problems without requiring you to install desktop software or trust a third-party server with sensitive files.
Our tool offers three distinct compression strategies. Low compression is completely lossless: it strips metadata fields like author name, creation date, and producer software, then re-saves the internal PDF structures using object streams. This alone can trim 5–15% from bloated files without touching a single pixel. Medium compression takes this further by optimising how the PDF engine serialises data, often achieving 15–30% reduction with negligible visual impact.
For situations where file size is paramount — email attachment limits, slow upload connections, or archival storage — High compression re-renders every page as a JPEG at 100 DPI and wraps the images in a fresh PDF shell. This can slash file size by 30–60%, but it converts vector text and graphics into raster images. Text is no longer selectable or searchable, so this mode is best reserved for when readability at screen resolution is acceptable and editability is not needed.
Because everything runs in your browser via WebAssembly and JavaScript, your documents never leave your machine. There are no server uploads, no cloud processing queues, and no file-retention policies to worry about. This makes the tool ideal for legal documents, financial statements, medical records, and any other PDF containing information you would rather keep private.