Reduce PDF file size locally in your browser using qpdf WASM. Choose standard or web-optimised compression, then download the new PDF.
Last updated: August 2026 | By Workshelve Team
Smaller PDFs are easier to email, upload, archive, and deliver through a website. Compression can reduce unnecessary internal data without changing the document's visible page content.
The amount saved depends on how the original PDF was created. Files that already use compressed images and efficient object streams may shrink only slightly.
This tool runs qpdf through WebAssembly. Your source PDF stays on your device while its streams and object structure are rewritten.
Standard mode applies structural compression. Web-optimised mode also recompresses Flate streams and linearises the file so its first page can begin loading sooner over the web.
Compresses eligible streams, generates object streams, and removes unreferenced resources.
Adds stronger Flate recompression and linearisation for PDFs intended for browser delivery.
No. The PDF is processed locally in your browser.
No. A PDF that is already efficiently compressed may shrink only slightly or could become marginally larger after rewriting.
This tool performs structural qpdf compression. It does not deliberately downsample or recompress embedded images as lower-quality JPEGs.
It linearises the PDF so a browser can begin displaying the first page before the entire file has downloaded.
No. The tool creates a separate compressed PDF and leaves the source file untouched.
Encrypted or restricted files may fail unless qpdf can open them without an additional password.
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