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PDFWix compresses PDF files by 40–90% using Ghostscript via WebAssembly — processing runs entirely inside your browser, so your file never leaves your device. No signup, no watermark, no file size cap.
PDFWix compresses PDF files by 40–90% using Ghostscript via WebAssembly — processing runs entirely inside your browser, so your file never leaves your device. No signup, no watermark, no file size cap.
Need a PDF under 100KB for a government job portal, visa application or exam form? Use the Strong compression preset. Most text-heavy PDFs compress well below 100KB. For image-heavy documents, try removing unnecessary pages first with Remove Pages, then compress.
WhatsApp allows PDFs up to 100MB. If your PDF exceeds this, use PDFWix Compress PDF to reduce file size. For scanned documents, the Strong preset typically reduces a 50MB scan to under 5MB.
Gmail's attachment limit is 25MB, Outlook is 20MB, and most corporate email gateways cap at 5-10MB. Use the Recommended preset to reduce size by 50-80% without visible quality loss. For PDFs still too large, split into smaller parts with Split PDF first.
Text and vector content is always preserved exactly — only embedded raster images are recompressed. At Low level, images are kept at up to 2400 px wide and re-encoded at high JPEG quality, which is visually lossless for almost all uses. Recommended caps images at 1600 px, and Strong caps them at 1000 px with a lower quality setting. If your PDF is text-only, the file shrinks only modestly because there is nothing image-shaped to recompress. See our guide: [how to compress a…
It depends entirely on the content. Image-heavy PDFs (scanned documents, photo portfolios, marketing decks) typically shrink 40–80%. Text-heavy and merged PDFs shrink 20–80% depending on how many duplicate streams and embedded resources they contain. PDFWix shows the exact before and after sizes on the download toast.
No artificial limit. Browser-based compression handles files up to your device's available RAM — typically several hundred MB on a modern laptop. Very large PDFs (500 MB+) will perform better on a desktop than on a phone.
Most likely it contains mostly text and vector graphics, which are already stored efficiently and cannot be shrunk further without removing content. PDFs that contain images encoded with less common formats (JPEG 2000, JBIG2, CCITT fax) are also skipped to avoid corrupting them — the toast tells you how many images were skipped. For scanned PDFs, try Strong compression.
Yes. PDFWix compresses files entirely in your browser — the PDF never leaves your device. There is no upload to any server, making it safe for confidential documents, contracts, and medical records.
Low compression keeps images up to 2400 px wide at high JPEG quality, which prints cleanly at letter size up to about 300 DPI. Recommended caps images at 1600 px (about 200 DPI on a letter page) — good for office printing. Strong is intended for screen viewing and email, not high-quality print.
For a complete overview of PDF workflows, see our guide to PDF work in 2026.
Quality depends on how aggressive the image downsampling and JPEG re-encoding is. PDFWix exposes three explicit levels (Low / Recommended / Strong) so you can choose the trade-off yourself, and we never touch text or vector content. iLovePDF, Smallpdf, and Adobe Acrobat Online use proprietary server-side pipelines that do not disclose their exact downsampling targets.
For most image-heavy PDFs, yes. A 10 MB scanned document typically lands around 2–4 MB on Recommended and 1–2 MB on Strong. Text-only PDFs are already compact and rarely shrink below 80–90% of the original size at any level.
Once compressed, you can merge PDF files or split PDF pages as needed. For a detailed comparison of compression techniques, see our guide: Best way to compress a PDF.