Why “under 100 KB” is so common
Many Indian government and university portals were built when upload bandwidth was precious, so they cap supporting documents at 100 KB, 200 KB or 500 KB. A single phone photo of a certificate is often 2–5 MB, and a normal JPG-to-PDF converter simply wraps that photo inside a PDF — the file stays large. To get under the limit you have to reduce two things at once: how many pixels each page keeps, and how strongly those pixels are compressed. Doing that by hand takes many attempts; this tool automates it.
How the tool chooses quality
For each candidate resolution (from about 2000 px down to 400 px on the long side) it runs a binary search on JPEG quality, builds the real PDF in memory and measures its exact size. It stops at the highest resolution that still allows reasonable quality within your target. The result panel shows the resolution and quality used, so you can judge whether it is good enough.
| Pages | Target | Typical outcome (clear phone photos) |
|---|---|---|
| 1 certificate | 100 KB | Sharp, easily readable |
| 2 pages (front/back ID) | 100 KB | Readable; slight softness when zoomed |
| 3–4 pages | 100 KB | Use black & white for best text clarity |
| 5+ pages | 200–500 KB | Better to use a larger limit if the portal allows |
These are typical results, not guarantees — dense small print and dark photos need more bytes.
Tips for sharp, small PDFs
- Photograph flat and straight. Place the document on a dark table, hold the phone parallel and fill the frame with the page.
- Use daylight, no flash. Shadows and glare waste bytes and hide text.
- Crop away the table. Every pixel of background eats into your 100 KB.
- Tick black & white for text documents. Colour is only needed for photos or coloured stamps the portal asks to see.
- Choose A4 for forms; “Same as image” is fine for single photos.
Uploading salary slips or bank statements for a loan? Work out the monthly instalment first with the EMI calculator on Calculator Hub.
Already have a PDF that is too big?
If you have a scanned PDF rather than JPGs, use the PDF compressor. To combine several PDFs first, use Merge PDF. For photos that need to be a specific KB on their own (not a PDF), use Photo Resize in KB.