PDF Compressor
Reduce your PDF file size in seconds. Choose your compression level, preview pages, and download the optimised result — no uploads needed.
Drop your PDF here
Drag & drop or click to browse. One PDF file at a time.
Choose PDF FileFree PDF Compressor — Reduce PDF Size Without Uploading
Shrink large PDF files right in your browser — no server, no account, no waiting. Choose from three compression levels, preview the pages before compressing, and see an exact before-and-after size comparison when your download is ready.
🔒 Private & Secure
Your PDF never leaves your device. All processing is done locally using JavaScript.
🎛️ 3 Compression Levels
Low, Medium, and High modes let you balance file size against output quality.
📊 Real Size Comparison
See the original size, compressed size, and exact percentage saved after every compression.
👁️ Page Preview
Thumbnails of the first pages are shown before you compress so you know what you're working with.
How to Compress a PDF
- Click Choose PDF File or drag & drop your PDF onto the upload zone.
- Page thumbnails appear in the preview area and the original file size is displayed.
- Select your preferred Compression Level — Low, Medium, or High.
- Click Compress & Download and wait a moment for the pages to be processed.
- Your compressed PDF downloads automatically. The size comparison is shown on screen.
How Does the Compression Work?
This tool rasterises each PDF page to a JPEG image at the chosen quality level using the HTML5 Canvas API, then embeds those images into a new PDF using pdf-lib. The result is a smaller file, with the trade-off that text is no longer selectable in the output — ideal for sharing visual documents, presentations, and image-heavy reports, but not recommended for forms or text-heavy contracts where searchability matters.
Frequently Asked Questions
Yes — completely free, with no usage limits and no account needed.
No. Everything runs client-side in your browser. Your file never leaves your device.
No — this tool converts pages to images, so text becomes part of the image. If selectable text is essential, use a dedicated server-side PDF optimiser instead.
Use Low for documents you need to look sharp (e.g. brochures, CVs). Use Medium for everyday sharing. Use High when file size is the only priority (e.g. email attachments with a strict size limit).
This can happen with PDFs that are already highly optimised, contain mostly vector graphics, or have very few images. In those cases the tool will warn you and still let you download the result.
There is no hard limit — processing depends on your device's available memory. Very large PDFs (100+ pages, 50 MB+) may be slow on low-end devices.