What fits in 100 KB
What fits in a 100 KB PDF, and in 50 KB
A hundred kilobytes sounds like a quality setting. It is really a page count, and the count depends on three things you control: the resolution above all, then grey or colour, then how dense the page is.
Measured, not guessed
The figures below were measured by putting one test page — a dense typed page photographed at an angle on a dark desk, 2400 × 1800 pixels — through this site’s own writer, the same code that makes your PDF, on A4 with a 10 mm margin, in Chrome. A real phone photo will land somewhere near them; the planner on the size pages measures your own photos, which is the figure to trust.
| One A4 page of a photographed text document | 72 DPI | 150 DPI | 200 DPI |
|---|---|---|---|
| Photographed as it is, grey | 36 KB | 99 KB | 137 KB |
| Photographed as it is, colour | 37 KB | 105 KB | 144 KB |
| Document mode on, grey | 52 KB | 143 KB | 187 KB |
| Document mode on, colour | 53 KB | 150 KB | 197 KB |
Reading the table
- Resolution is the lever. Going from 200 to 72 DPI took this page from 137 KB to 36 KB. Every other setting moved it by a few per cent.
- Grey helps most on colourful pages. This test page is already nearly grey, so grey saved only about 5 %. A certificate with coloured borders and seals saves more.
- Document mode is for legibility, not size. Squaring and whitening the page made it heavier here, because the page then fills the sheet and the ink edges are sharper. It is what makes a 72 or 150 DPI page readable; pair it with the ceiling.
- 150 DPI is where small print stops being readable. Below it, text on A4 goes soft. 72 DPI is screen resolution: fine for a photo, poor for a form.
So, for a 100 KB limit
A page as dense as this one fits once at 150 DPI and two or three times at 72 DPI. A lighter page — a certificate that is mostly white space — fits more. A colour photo of a scene takes most of the budget on its own. For 50 KB, think one page at a lowered resolution.
If the portal takes several files, the Save step can write one PDF per photo, each under the limit. If it takes one file, fewer pages is the honest answer — the builder will not write a file it has crushed below legibility to hit a number; it states the closest size it reached instead.
Start from JPG to PDF under 100 KB, which opens with these settings, or under 200 KB for the larger limit; the India upload limits lists the figures real portals state.