Compress PDF to 100 KB
Reduce a PDF to 100 KB or less for an online form or email. Keeps the best quality that fits, and your document never leaves your device. Free.
- Files stay on your device
- Free, no sign-up
- Updated
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Choose your PDF and click Compress PDF: the tool makes it 100 KB or smaller while keeping the best quality that fits. It first tries lossless compression; if that isn't enough, pages are saved as optimised images. Your document is processed in your browser and never uploaded.
How to use the Compress PDF to 100 KB
- Choose or drop your PDF.
- Keep the target at 100 KB (or change it) and pick colour or black & white.
- Click Compress PDF, then Download PDF.
Why compress a PDF to 100 KB?
A 100 KB limit is common on job, exam and government portals that only accept small document uploads. One or two scanned pages usually fit at readable quality. For longer documents, choose Black & white — it often halves the size — or upload only the pages that are asked for.
How big is 100 KB?
| 100 KB (1 KB = 1,000 bytes) | 100,000 bytes |
|---|---|
| 100 KB (1 KB = 1,024 bytes) | 102,400 bytes |
| This tool aims for | 100,000 bytes or less |
Forms don't agree on whether a kilobyte is 1,000 or 1,024 bytes. Staying at or under 100,000 bytes passes both.
What happens to your PDF
| Step | What it does | Text stays selectable? |
|---|---|---|
| 1. Lossless | Rewrites the PDF more efficiently. Nothing changes visually. | Yes |
| 2. Images (only if needed) | Each page is saved as an image at the highest resolution and quality that fits 100 KB. | No — the pages look the same, but text can't be selected or searched |
Tips for a smaller PDF
- Choose Black & white for scanned letters and forms — it is much smaller than colour.
- Remove blank or extra pages before compressing.
- If you scan, 150–200 DPI is enough for documents; 600 DPI scans are huge.
Frequently asked questions
Are my files uploaded to a server?
No. Everything happens inside your browser, so your documents never leave your device. That makes it safe for private files like contracts, IDs and bank statements.
Does it work with password-protected PDFs?
No. Open the PDF with its password in a PDF reader, save or print it to a new PDF without a password, then use that copy.
What if my PDF can't get under 100 KB?
The tool tells you the smallest size it could reach and still lets you download it. Try Black & white, remove pages you don't need, or split the document and upload the parts separately.
Will my text still be selectable?
Yes, if lossless compression is enough. If pages have to be turned into images to reach the size, they look the same but the text can no longer be selected or searched.
Is there a page limit?
Up to 200 pages. Larger documents are slow to process on a phone — split them first.
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