How to compress a PDF under 100 KB or 200 KB for online forms
Government recruitment forms, university admissions and scholarship portals usually set a strict size limit for each document: 100 KB, 200 KB, 300 KB or even 50 KB. A scanned mark sheet straight from a phone can easily be 2 to 5 MB, so the portal says "File size exceeds the limit" and won't let you continue. This guide shows how to bring a PDF under the limit without making it unreadable.
Why scanned PDFs are so large
A PDF made from a phone photo or a scanner is really a set of pictures, one per page. The size depends on three things: how many pages there are, how many pixels each picture has, and how much each picture is compressed. A modern phone camera takes 12 to 50 megapixel photos, far more detail than a form needs. Reducing that detail is what brings the size down.
Step by step
- Open the Compress PDF tool and select your PDF. It is processed in your browser, so a confidential document such as an Aadhaar card or mark sheet is never uploaded.
- Choose a target size, for example "under 100 KB", or pick a compression level.
- Download the result and open it before you upload it. Zoom in on small text such as roll numbers and dates to make sure it is still readable.
- If the text is blurry, try a slightly larger target (for example 180 KB instead of 100 KB when the limit is 200 KB).
Tips when the file still won't fit
- Remove pages you don't need. Many forms want only the front page of a certificate. Use Delete PDF pages or Extract PDF pages first. Every page removed saves space.
- Crop the photo before making the PDF. A photo with a table and background around the document wastes space on parts nobody needs.
- Scan in black and white or greyscale when colour isn't required. Colour pages are much bigger.
- Start from a good scan. Shadows, folds and uneven light make files larger and harder to read. Lay the document flat near a window and hold the phone straight above it.
Common size limits
Every organisation sets its own rules, and they change from one notification to the next, but you will often see limits like these:
| Document | Typical limit |
|---|---|
| Certificates, mark sheets, caste or income certificate | 100 KB to 500 KB, PDF |
| Identity proof (Aadhaar, PAN) | 100 KB to 300 KB, PDF or JPG |
| Experience letters, NOC | 200 KB to 1 MB, PDF |
Always check the official notification. If it says "between 50 KB and 100 KB", a file that is too small will also be rejected.
Photos and signatures
Passport photos and signatures usually have their own, much smaller limits and must be JPG files. See our guide on resizing a photo and signature for government forms.