Form specifications
Official form requirements
A platform limit is one number. A form specification is a byte cap plus pixel dimensions, plus a format, and often a floor as well as a ceiling — which is the half every other compressor fails, since “as small as possible” is itself a rejection when the form demands a minimum too. These pages carry the whole specification, and say plainly which parts compressing cannot fix.
Last verification pass 10 Oct 2026
1 specification
Verified against a primary source
Each page opens the compressor at the ceiling, which clears the floor at the same time.
Not here
Specs we will not publish, and why
This category is full of numbers copied between blogs and resizer tools. A confidently wrong figure on a visa application is worse than no page, so these stay out until a primary source states them.
UPSC and SSC photo and signature specs
Consistently reported as 20-200KB and 20-100KB, but only by third-party blogs and competing resizer tools. These live in per-cycle notice PDFs that change every exam cycle, so the figure needs to come from a current notice on the commission's own site before it can go on a page here.
Canvas, Moodle and Blackboard
No universal number exists. The upload cap on a learning platform is set per institution by whoever administers it, so every published figure for them is somebody's local setting presented as a global fact. If your course has a limit, it is in your own course settings.
LinkedIn profile photos
Reported at 8MB, again only secondarily. It is also not a constraint anybody needs a compressor for, so it would be a page about a problem nobody has.
If your form gave you a number, you do not need our table — set it yourself and the output is measured against it before you are handed the file.