🗜️ Compress PDF WASM
Reduce PDF file size dramatically without leaving your browser. Pick a compression level, preview the result, and download.
Upload PDF
Drop your PDF below — everything runs locally, nothing is uploaded.
Drop your PDF here or click to browse
Only .pdf files • Works offline • Your file never leaves this device
document.pdf
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Preview (page 1)
Shows exactly how the first page will look at your chosen settings.
How to Compress a PDF
Upload Your PDF
Drop your file into the box above. It stays on your device.
Pick a Level
Choose a preset — or go Custom and set exact DPI and quality.
Download
See the before/after sizes, then download your compressed PDF.
Frequently Asked Questions
Yes — but how much depends on the level. Light is virtually indistinguishable from the original for most documents. Balanced works well for everyday sharing. Extreme produces the smallest file but noticeably softens images and small text.
No. To achieve the smallest possible file size, this tool rasterizes every page — it renders each page as a high-resolution image and rebuilds the PDF from those images. That makes text non-selectable and non-searchable. If you need to keep selectable text, use our Remove Metadata or Linearize PDF tools instead, which reduce size without rasterizing.
No. Everything runs in your browser using pdf.js and pdf-lib. Your file never leaves your device. You can even run this tool offline after the page has loaded once.
This can happen with PDFs that are already heavily optimized, or with pure-text documents that contain no images. When it does, we'll show you a warning and offer the original for download instead — no reason to give you a worse file.
There's no hard limit, but very large PDFs (100+ pages) may use significant memory and take a minute or two. For best results on mobile, keep files under ~50 pages or use a lower DPI setting.