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MondayKit

Compress PDF online – private and free

Make scanned PDFs smaller with High, Medium or Low quality, or a target size in KB.

Processed in your browser. Files are never uploaded.

or drop a file here

How to compress PDF online – private and free

  1. Drop a PDF into the box, or click to choose it.

  2. Pick a quality preset (High, Medium or Low) or switch to a target size in KB.

  3. Click Compress PDF and wait while each page is rebuilt.

  4. Check the new size and click Download.

  • No upload

    Your files are processed on your device and never sent anywhere.

  • Free, no signup

    No account, no watermark and no daily limit.

  • Fast

    No upload or download wait – results appear in seconds.

What is Compress PDF?

Compress PDF makes PDF files smaller so they fit through upload limits on job, exam and government portals, and travel lighter as email attachments. It works best on scanned documents and photo-heavy PDFs, which are often many times larger than they need to be.

How it works

Each page is rendered in your browser with pdf.js, saved as a JPEG at the resolution and quality you choose, and placed into a new PDF with pdf-lib. High keeps 150 DPI for print-friendly results, Medium uses 110 DPI for a good balance, and Low uses 72 DPI for the smallest file. In target mode the tool tries progressively smaller settings and stops at the first one that fits.

Be aware

  • Text will not be selectable afterwards, because every page becomes an image. Links, bookmarks and form fields are not kept.
  • Already-optimised PDFs may not shrink. Documents exported from Word, Google Docs or a website are usually compact already; we tell you if the result is not smaller.
  • Keep your original file for editing and records.

Need to hit a specific limit? Use the presets for 200 KB, 100 KB, 500 KB or 1 MB. To shrink by removing pages instead, try Delete PDF pages or Split PDF.

Frequently asked questions

How does MondayKit compress a PDF without uploading it?

Your browser renders each page with pdf.js and rebuilds the document from JPEG images with pdf-lib. Both libraries load only when you first use the tool, and the file never leaves your device.

Will my text still be selectable?

No. Pages become images, so text cannot be selected, searched or read aloud afterwards, and links and form fields are removed. Keep your original for editing.

Why did my PDF not get smaller?

PDFs exported from Word or other apps are mostly vector text and already compact. Turning them into images can make them larger. The tool warns you when that happens – keep the original.

Can I compress a PDF to a specific size like 200 KB?

Yes. Choose Target size (KB) and enter the limit. We step down resolution and quality until the file fits, or tell you the smallest size we could reach.

Is there a page or size limit?

There is no fixed limit, but every page is redrawn on your device, so very large scans take longer and need more memory. Files over 100 MB show a warning.

Related tools

Merge PDFCombine multiple PDFs into one file in the order you choose.Split PDFSplit a PDF into single pages, custom ranges or equal parts.Delete PDF pagesRemove unwanted pages from a PDF file.JPG to PDFTurn JPG, PNG or WebP images into a PDF document.Compress imageShrink JPG, PNG and WebP file size with a quality or target size.

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