This PDF compressor shrinks large PDFs, such as scanned certificates, photo-filled reports or phone scans, so they fit under upload limits on job portals, college forms and email. It runs in your browser, and the file is not uploaded anywhere.
How to use the PDF compressor
- Choose a PDF from your device.
- Pick a level: Small file for the smallest size, Better quality for sharper pages, or Balanced in between.
- Wait while each page is processed. Long documents take longer, because every page is redrawn.
- Compare the before and after sizes. If the new file is smaller, download it. If it isn’t, the tool tells you so and offers your original file instead.
How it works, and an important limit
A PDF page can hold real text with fonts, vector drawings and pictures, all described separately. The Library of Congress format description sums PDF up as a page-oriented format that can contain text, images and graphics; today it is an ISO standard (ISO 32000-2 for PDF 2.0).
This tool does not edit those parts one by one. Instead it draws each page as a picture, saves that picture as a JPEG, and builds a new PDF from the pictures. The level you choose decides the resolution and JPEG quality of those page images.
Watch out: Because every page becomes an image, the text in the compressed PDF can no longer be selected, copied or searched, and links inside the document stop working. Keep your original file. Do not use this for documents that need searchable text, form fields or a digital signature.
When this PDF compressor works well
| Type of PDF | Expected result |
|---|---|
| Scanned pages (marksheets, ID proofs, signed forms) | Usually a good saving – the pages were images already |
| Brochures and reports full of photos | Often a good saving |
| Text-only PDF exported from Word or Google Docs | Often larger, and text becomes unselectable – not recommended |
| Already compressed or very small PDFs | Little or no saving; the tool will offer the original |
A text-only PDF is tiny because it stores letters and font data, not pixels. Turning those pages into images usually makes the file bigger, not smaller. That is why the tool always compares sizes and never forces a worse result on you.
Choosing a level
- Small file: best for meeting strict limits, such as a 200 KB or 500 KB cap on an application form. Zoom in on the result and check that small print is still readable.
- Balanced: a sensible default for sharing scans by email or chat.
- Better quality: for documents with fine print, stamps or signatures that must stay clear.
Tip: If one level is still over a size limit, try the next level down. If the pages started as phone photos, you can also shrink the photos first with the image compressor and rebuild the PDF with JPG to PDF.
For background on why JPEG suits photo-like pages, see web.dev’s guide to JPEG, and our post on image optimization for the web.
Learn more
- PDF to JPG Converter
- JPG to PDF Converter
- Image Compressor
- Image Optimisation for the Web: Formats, Sizes and Lazy Loading
- HTML Images
Frequently asked questions
Is my PDF uploaded to a server?
No. The PDF is opened and rebuilt inside your browser, and the new file is created on your device.
Why can't I select text in the compressed PDF?
Each page is saved as a JPEG image inside the new PDF. An image of text looks the same but is not text any more, so it can’t be selected, searched or copied. Keep the original for that.
The compressed file is bigger than my original. Why?
This happens with text-based PDFs, which are already small. The tool spots it, tells you, and offers the original so you don’t download a worse file.
Can I compress a password-protected PDF?
This tool needs to open and read every page. If your PDF needs a password to open, remove the protection in your PDF reader first, and only if you are allowed to.