How to compress a PDF to 100KB
- 1. Add your PDF. Drop it in or click to browse. The target is already set to 100KB.
- 2. Click Compress. SlimIO first tries a text-preserving compression. If the file is still too big, it lowers image resolution step by step until it fits.
- 3. Download. You get the sharpest version that is under 100KB.
Where the 100KB limit shows up
Online job applications, exam registrations and government service portals often cap each upload at 100KB — usually for scanned certificates, ID proofs, mark sheets or signed forms.
What realistically fits in 100KB
One or two scanned pages compress well to 100KB and stay readable. A text-only PDF made from Word is often already under the limit. A long scan of 10+ pages will fit only at low resolution, and small print may blur.
Tips for a clearer result
- Upload only the pages the form asks for — use Remove Pages or Split PDF first.
- If you are scanning, choose grayscale at 150–200 dpi. Color scans take far more space.
- Crop away empty margins before scanning where you can.
Compress PDF to 100KB — FAQ
How do I compress a PDF to 100KB for free?
Open this page, drop in your PDF and click Compress. The target is preset to 100KB. SlimIO keeps the best quality that fits and the file downloads right away — no signup or install.
Why is my PDF still over 100KB?
Very long or very detailed scans can't always get under 100KB and stay legible. SlimIO then gives you the smallest version it could make. Remove pages you don't need, or split the file and upload the parts separately.
Will the text still be readable at 100KB?
For one or two pages, yes. SlimIO lowers resolution only as much as needed to reach the target, so short documents stay clear.
Can I still select or copy text after compressing?
If the text-preserving step reaches 100KB, yes. If pages have to be turned into images to hit the target, the text is no longer selectable — the result tells you which one happened.
Is it safe to compress my documents here?
The image step runs entirely in your browser. The text-preserving step sends the file to our server over HTTPS and deletes it as soon as it is compressed; nothing is kept.