Large PDF files cause email bounces, slow uploads, and storage problems. Whether your PDF is 50 MB, 100 MB, or larger, here's how to reduce its size dramatically in your browser — with no file size limits and no uploads to any server.
PDFs grow large primarily because of high-resolution embedded images, uncompressed scanned pages, and accumulated metadata from repeated editing. A 10-page scanned document can easily reach 50–100 MB when each page is stored as a 300 DPI uncompressed image.
Go to pdfeditor.onl/compress-pdf. Close other browser tabs first to free up RAM for processing the large file.
Tip: For files over 80 MB, use Chrome or Firefox on a desktop or laptop rather than a mobile browser for the most reliable processing.
Drag the large PDF onto the upload area or click to browse. The file loads into your browser's local memory — processing happens entirely on your device.
For large files where reducing size is the priority, select Strong compression. This typically reduces file size by 60–90%. Click Compress Now and wait — large files may take 20–60 seconds to process depending on your device.
The result panel shows the original size, compressed size, and percentage saved. Click Download Result. If you need even more reduction, try splitting the PDF first, compressing each part separately, then merging.
There is no artificial limit. Files up to 200 MB are commonly processed. For very large files, ensure you have at least 2–3× the file size in available RAM.
For a typical scanned document, Strong compression typically brings a 100 MB file down to 10–20 MB. Results vary depending on image content and resolution.
On a modern desktop, expect 10–30 seconds for a 50 MB file. On older devices or mobile, it may take 1–2 minutes. The browser will not freeze — processing runs in a background WebAssembly thread.