Compress PDF image resolution and quality 100% locally in your browser with size comparison and zero leak risk.
Drag & drop PDF file here, or click to upload
Compress PDF image resolution and quality 100% locally in your browser with size comparison and zero leak risk. Use it for everyday work, development, learning, or quick verification.
This tool runs in your browser. Before working with sensitive data, make sure you trust your browser and device environment.
This PDF compressor works by re-rendering every page as an image and rebuilding the document. After you upload a file, PDF.js draws each page at the resolution you choose (72–300 DPI, 150 by default), the page is encoded as a JPEG (quality 10–100%, 60% by default), and pdf-lib assembles a new PDF with the original page sizes. You then see the original size, the new size and the percentage saved before you download the result, named compressed_yourfile.pdf. The file is processed in your browser and never uploaded.
This approach works best on scanned documents and PDFs full of photos: phone-scanned contracts, lecture notes made from pictures, or catalogs with high-resolution images often shrink by half or more, small enough to email or to fit an upload limit. DPI controls sharpness. For on-screen reading and ordinary printing, 150 DPI is usually enough; 100–120 DPI is fine for screen-only use, and 200–300 DPI helps when small print must stay legible on paper. Lower quality means a smaller file but softer, blockier text edges.
Keep in mind that the output is an image-only PDF. Text you could previously select, copy or search becomes part of a picture, and hyperlinks, bookmarks, form fields and annotations are not kept. A text-based PDF exported from Word or a slide deck is already small, so turning it into images can actually make it bigger; the tool then shows the real, larger size and a negative saving, and you are better off keeping the original.
The tool handles one file at a time. Many pages or a high DPI need more memory and time, so on phones start at 150 DPI or lower. Password-protected PDFs cannot be opened directly; remove the password first with the PDF password remover tool using the password you know, then compress. The PDF.js and pdf-lib libraries load from a CDN, but your document is only processed locally.
Usually because the original is a text or vector PDF, such as a report exported from Word. Its text is stored as fonts and takes very little space; replacing each page with an image adds data. This tool is meant for scans and image-heavy PDFs, so in that case simply keep the original file.
No. Every page becomes an image, so text, links, bookmarks and form fields are not preserved. Keep the original if you need searchable text, or run OCR on the compressed file afterwards.
Start with the defaults, 150 DPI and 60%. For email attachments or screen reading, try 100–120 DPI at around 50%. For printing, or pages with small text and tables, use 200 DPI or more at 70–80%. Compare the resulting size after each run and pick the best balance.
No. The PDF.js and pdf-lib code is downloaded from a public CDN into your browser, but the PDF itself stays in browser memory and the compressed file is generated and downloaded locally without passing through any server.
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