invisible character checker

A free tool that finds and cleans up "invisible characters" (zero-width spaces, full-width spaces, NBSP) and confusing full-width alphanumerics that sneak in through copy-paste, right on the spot.

"Rejected by forms," "doesn't show up in searches," "code won't run"—when you're stuck without knowing the cause, this tool visualizes invisible characters that are often the culprit.

・Your input is never sent anywhere (everything is processed in-browser with JavaScript)
・Individually detects and highlights zero-width spaces, full-width spaces, NBSP, and more
・Select found characters and remove them with one click

Use it for pasting inquiry text, copy-pasting code, checking manuscripts, and more.