Two clear compression modes
Choose stronger size reduction or preserve the original image streams without additional JPEG compression.
Free local PDF compressor
Compress PDF online
Reduce PDF file size without uploading it to a server. Choose balanced image compression or lossless optimization for the document structure.
Private Free No installation
Document structure preserved
Text remains text, vector elements stay vector, and links or forms are not replaced with flat page images.
Local processing
Neither the PDF nor the result is sent to a server. qpdf/WASM runs in an isolated browser worker with a time limit.
4 simple steps
How to reduce PDF file size
DocFlip runs qpdf in a separate Web Worker. Processing stays local, and text, links, forms, and vector graphics are not flattened into page images.
- 1
Choose a PDF
Add one document up to 50 MB. The file remains in your browser memory.
- 2
Choose a mode
Balanced mode may recompress suitable images; lossless mode changes only the packaging of streams and objects.
- 3
Start compression
The WebAssembly engine removes unused objects and rewrites the PDF structure compactly in a separate worker.
- 4
Compare and download
DocFlip shows the before and after sizes. If the result is larger, it will not offer an unhelpful file.
DocFlip
Real PDF optimization without rasterizing every page
The tool rewrites the document structure and, in balanced mode, optimizes suitable images. It does not create screenshots of every page.
Two clear compression modes
Choose stronger size reduction or preserve the original image streams without additional JPEG compression.
Document structure preserved
Text remains text, vector elements stay vector, and links or forms are not replaced with flat page images.
A result only when it saves space
Some PDFs are already optimized. DocFlip compares the sizes and will not offer a result that is larger than the source.
Local processing
Neither the PDF nor the result is sent to a server. qpdf/WASM runs in an isolated browser worker with a time limit.
FAQ
PDF compression questions
How do I compress a PDF online for free?
Add a PDF up to 50 MB, choose balanced or lossless mode, and select “Compress PDF.” No account or payment is required.
What is the difference between the two modes?
Lossless mode repacks streams and objects without changing images. Balanced mode can also convert suitable non-JPEG images to JPEG, but only when that makes them smaller.
Does DocFlip turn PDF pages into images?
No. The tool does not rasterize the entire document, so it preserves editable structure, text, vectors, links, and forms as supported by the source PDF.
Why did the PDF not become smaller?
It may already be optimized, contain mostly JPEG images, or have little redundant structure. Additional repacking cannot reduce every file.
Does compression reduce image quality?
Lossless mode does not. Balanced mode may use JPEG for suitable images, so a small image-quality change is possible.
Can I compress a password-protected PDF?
An encrypted PDF may require a password and fail to process. Remove protection lawfully in an application where you know the password first.
Is the PDF uploaded to a server?
No. The file is read locally, processed by qpdf in WebAssembly, and stays on your device.
More PDF tools
Change the page set or order before sharing a document.