Compress PDF

Reduce PDF file size online — shrink big PDFs in your browser.

Compress a PDF to a smaller file size right in your browser — perfect for emailing, uploading to portals and sharing on chat. Choose from three levels (less, recommended or extreme compression), and each page is re-rendered and re-encoded at your chosen quality, which cuts scanned and image-heavy PDFs dramatically. See the before/after size before you download. 100% in-browser — nothing is uploaded, no sign-up, no watermark.

Compress PDF features

• Reduce PDF file size in your browser
• Three compression levels — quality vs. smallest size
• Great for scanned and image-heavy PDFs
• See original vs. compressed size before download
• No upload, no watermark, no sign-up

How to use Compress PDF

1. Upload your PDF

   Drop a PDF into this free online compress PDF tool or click to select one — it loads instantly in your browser with nothing uploaded to any server.

2. Pick a compression level

   Choose Less, Recommended or Extreme compression depending on whether you care more about keeping quality high or making the file as small as possible.

3. Compress

   Click Compress PDF and each page is re-rendered and re-encoded locally, with a live progress percentage so you can see how far along the compression is.

4. Check the savings

   The tool shows the original size, the new size and the percentage saved, so you can confirm the reduction is worth it before you download anything.

5. Download the smaller PDF

   Click Download compressed PDF to save the reduced file to your device — ready to email, upload to a portal or share on chat without hitting size limits.

Frequently asked questions

How do I compress a PDF for free?

Drop your file into this tool, choose a compression level and click Compress PDF. There's no sign-up, no watermark and no file-size limit — and the whole thing runs in your browser.

How much smaller will my PDF get?

It depends on the file. Scanned documents and image-heavy PDFs often shrink by 50–80%. PDFs that are already optimised or purely text may not shrink much — the tool will tell you and let you keep the original.

Will the text stay selectable?

No. Browser-side compression works by flattening each page to a compressed image, so selectable text becomes part of the picture. If you need the text to stay selectable, keep your original file.

Is my PDF uploaded to a server?

No. Rendering (pdf.js) and rebuilding (pdf-lib) happen entirely on your device. Your document is never uploaded, logged or stored.

Does compressing a PDF work on mobile?

Yes. Because everything runs in your browser, you can compress a PDF on a phone, tablet or desktop with no app to install — just open the page and drop in your file.

Why is my compressed PDF not smaller?

Your PDF was probably already well optimised, or it's mostly plain text (which is tiny to begin with). In that case re-encoding the pages can't beat the original, so it's best to keep the file you have.

How do I compress a PDF to email it?

Pick the “Recommended” or “Extreme” level and compress — most scanned or image-heavy PDFs shrink enough to slip under common email limits (often 25 MB). You'll see the before/after size, so you can pick the smallest level that still looks acceptable.

Which compression level should I choose?

Start with “Recommended” for a good balance of size and quality. Use “Less” when you want to preserve maximum clarity, and “Extreme” when you need the smallest possible file and can accept softer images. The size preview lets you compare before downloading.