The guides
The reasoning behind the settings
The builder has about a dozen controls and three of them regularly decide whether a document is accepted: the sheet, the margin and the ceiling on resolution. These guides are the arithmetic behind those three, written out once so the tool does not have to explain itself in tooltips.
Nothing here is a tour of the interface. Each one starts from a situation somebody actually arrives in — a rejected upload, a form that names a paper size, a field asking for a figure in dots per inch — and works through what the numbers mean until the setting to change is obvious. They are short, and they are meant to be read once.
Getting under 200 KB
Three settings decide how heavy the finished document is, and they only work in one order — pull them the other way round and you get a small file nobody can read.
Read this one if a portal has already refused your upload and given you a number.
Paper sizes and margins
A4, Letter and Legal in millimetres, what each margin takes off the box the photograph has to live in, and how much white a photograph of the wrong shape leaves behind.
Read this one before you choose the sheet, not after the pages come out wrong.
Dots per inch for form uploads
Why DPI is a relationship between pixels and paper rather than a property of a photograph, and the pixel counts that 200 and 300 come to on the sheets this builder offers.
Read this one if a form asked for a figure and your phone has no idea what it means.
What fits in 100 KB
Measured page weights in grey and colour at three resolutions, and what they mean for a 100 KB or 50 KB limit.
Read this one before you try to fit three certificates into one small upload.
India upload limits for PDFs
The file-size and format rules for myAadhaar updates, DigiLocker, NEET, UPSC and a mission's passport uploads, each with its source and the date it was checked.
Read this one when a portal states a figure and you want to know where it came from.
Photograph a document properly
Light, angle and distance for a phone photo of paper that turns into a clean, readable PDF page.
Read this one before you photograph the pages, not after.
Copied or redrawn
When a JPEG goes into the PDF byte for byte, when it has to be redrawn, and how to check your own file with free tools.
Read this one if you care whether a converter recompressed your photos.
If you would rather just build the thing
The reading is optional. The builder opens on the front page with everything at a sensible starting point, and four of its settings have a door of their own: A4 with a 20 mm margin, a long set in a fixed order, four photographs to a page, and a document that has to come under a figure. Every setting is reachable from every one of them; the doors only decide where you land.