How to compress a PDF to 100 KB
- Tap "Add a PDF" or drop it onto the box. "Under a set size" and 100 KB are already chosen.
- Tap "Compress PDF".
- Check the new size, then download the PDF.
Good to know
The photos and scanned pages inside the PDF are made smaller step by step until the file is under 100 KB. Text, fonts and drawings are left exactly as they are.
If that still isn’t small enough, the pages are saved as images to reach 100 KB. The text then can’t be selected or searched, and we tell you when this has happened.
We count 1 KB as 1,000 bytes and 1 MB as 1,000,000 bytes, so the file also fits forms that count in 1,024s.
Questions
Why is 100 KB so hard to reach?
A page of text is small, but every photo or scan in a PDF adds a lot. For a scanned document, 100 KB often means saving the pages as images at a lower quality. Try 200 KB if the result is hard to read.
Will the text still look sharp?
Yes, unless the pages had to be saved as images to reach the size. In that case the result says so, and you can try a bigger size instead.
Can I compress a password-protected PDF?
Remove the password first with our Unlock PDF tool (you need the password), then compress it here.
How big a PDF can I add?
Up to 50 MB, free and without an account. Free accounts, coming soon, will take PDFs of up to 100 MB.
Is my PDF uploaded?
No. Your PDF is compressed by your browser on your device. Nothing is sent to us.
Page last reviewed 23 October 2026.