Compatibility
Browser support and practical limits
KissPDF depends on modern browser features including WebAssembly, Web Workers, typed arrays, Canvas, Blob downloads, and the File API. Available memory matters as much as the file size.
Current verification status
The automated end-to-end suite currently runs in Chromium and verifies real downloads for all main tools. It checks page count, page dimensions, ordering, ZIP contents, password protection, unlocking, color inversion, and WebAssembly compression.
Current Chrome and Edge are the most directly covered browsers because they share Chromium. Firefox and Safari are intended targets, but this page does not claim a complete release matrix until the same workflows have been run there.
File size and memory
Desktop browsers
Compress PDF applies a 200 MB input limit. Other tools are still constrained by browser memory even when they do not display a fixed limit.
Mobile browsers
Compress PDF applies a 64 MB input limit. Complex pages can consume several times the compressed file size while being decoded or rendered.
Raster operations
PDF to JPG, PDF to PNG, and Invert PDF create full-page pixel buffers. Page dimensions and page count can matter more than the PDF file size.
Compression
The WebAssembly compression engine requires memory in addition to the input and output PDF buffers. Close memory-heavy tabs before processing a large file.
Troubleshooting
- Update the browser and retry in a normal tab rather than an embedded webview.
- Close other memory-intensive tabs or applications.
- Split a very large PDF and process smaller ranges.
- Unlock an opening-password PDF before using page tools.
- Keep the tab active while a mobile device is processing a large document.