Live Character Counter + Validation

Medium

javascriptformsdom

Build a text input with a live character counter (e.g. "42/140") that updates as the user types, and turns red once they exceed a 140-character limit. Add a submit button that's disabled while over the limit.

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The counter updates on every keystroke, not just on submit
The counter visually changes color (e.g. to red) once the limit is exceeded
The submit button is disabled while over the limit, and re-enabled once back under it
Works correctly if the user pastes text in, not just types it

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