Quick answer
To compress a PDF to 100, 200 or 500 KB, open Compress PDF, choose Strong, turn on grayscale for black-and-white documents and download. If it's still too big, remove extra pages or rebuild the PDF from a smaller photo. One clear scanned page usually fits under 200 KB.
Why do Indian portals ask for such small PDFs?
Exam, recruitment, scholarship, university and government service portals handle lakhs of uploads during peak dates. To keep them fast, they set strict limits — commonly somewhere between 50 KB and 2 MB per document. A phone scan of one certificate is often 2–5 MB, so it gets rejected.
Always check the official notification or the upload screen for the exact limit and format. Limits differ by portal and even by document on the same form.
How do I compress a PDF to under 100 KB?
- Open Compress PDF and add your file.
- Choose Strong.
- Turn on Convert to grayscale if the document is black and white (marksheets, certificates, ID copies).
- Download and check the size in your file manager.
A single scanned A4 page usually lands well under 100–200 KB this way. Multi-page files may need the extra steps below.
What size can I expect?
| Document | Typical original | After Strong + grayscale |
|---|---|---|
| 1-page certificate (phone scan) | 2–4 MB | 80–200 KB |
| Aadhaar front + back | 1–3 MB | 60–150 KB |
| 3-page marksheet set | 4–8 MB | 200–500 KB |
| 10-page document with photos | 10+ MB | 1–2 MB |
These are rough ranges — the real result depends on how the file was scanned.
What if it's still over the limit?
- Too many pages? Keep only the pages the portal asks for with Extract pages.
- One huge photo inside? Rebuild the PDF from a smaller photo with Images to PDF.
- Not sure what's heavy? Why is my PDF big? shows whether images, fonts or something else is taking the space.
- Need one file per document? Split PDF the combined file.
How do I make sure it's still readable?
Open the compressed PDF and zoom to 100%. Check roll numbers, dates, marks, signatures and stamps. If anything is blurry, use Balanced instead of Strong. A rejected or unreadable upload costs more time than a slightly bigger file.
Your marksheets, certificates and ID copies are compressed on your own phone or laptop. Nothing is uploaded to us.
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