How to compress a PDF to 100 KB
- Click Select PDF file or drop your PDF onto the page.
- The target is already set to 100 KB. Change it if your limit is different.
- Tick Black and white for text documents to make room for more pages.
- Click Compress to 100 KB and download. The result screen confirms whether the file is within the limit.
When you need a 100 KB PDF
100 KB is the strictest common limit, used by many exam, scholarship and government portals for certificates, mark sheets, caste and income certificates, and ID proofs. Uploading a larger file fails with errors such as "File size exceeds the maximum limit", and scans straight from a phone are often 2–10 MB.
How the 100 KB target is reached
For a one-page scan, 100 KB is easy: the tool usually lands around 96–110 DPI, which keeps printed text sharp on screen. For two or three pages it may need to go lower. Ticking Black and white roughly doubles the number of pages that fit. The tool tries settings from sharpest to smallest and stops at the first that fits, so you never get a file that is worse than it needs to be. If even the smallest readable setting is too big, it tells you and gives you the smallest version instead of an unreadable one.
Check before you upload
Open the downloaded PDF and zoom to 100% on the page with the smallest text, such as a certificate number, date or stamp. If it is readable on your screen, the reviewer will be able to read it too. If not, remove a page you don't need and compress again, or untick Black and white if a coloured stamp or photo became unclear. For more ways to get under a limit, see how to make a PDF smaller for upload forms.
Good to know
- Pages are re-saved as optimized images, so text can no longer be selected or searched. Keep your original.
- Page size and order stay exactly the same.
- Password-protected PDFs must be unlocked first.
Other sizes: 100 KB, 200 KB, 500 KB, 1 MB, or the full PDF Compressor. For photos, use Compress Image to 100 KB. Your PDF is processed on your device and never uploaded.
Frequently asked questions
Can a multi-page PDF fit in 100 KB?
Usually up to about 3–4 pages of typed text in black and white. Photos and colour pages take much more space. If it doesn't fit, remove pages you don't need or upload them separately.
Will my certificate stay readable at 100 KB?
Yes for normal certificates and mark sheets. Very small print, such as footnotes on a dense page, may soften; zoom in on the result before uploading.
Why not just reduce the PDF's quality in my scanner app?
Scanner apps rarely let you choose an exact size. Here you type 100 and the tool finds the best quality that fits.