Unicode Inspector lists every code point in a string: its U+ hex value, how many bytes it takes in UTF-8, its general category, and its script.
It also flags the things that cause trouble: invisible characters, control characters, and text that mixes scripts the way a lookalike domain does. It runs in your browser.
This tool counts code points. Editors often count UTF-16 units, so an emoji or other character above U+FFFF shows as two there and one here.
No full name database is bundled, to keep the tool small. It names a set of common invisible and control characters and gives the code point for everything else.
Text that mixes, say, Latin and Cyrillic letters can spell a word that looks normal but is not, which is how some phishing domains work.
No. The analysis runs in your browser.