Check if the character represented by a given Unicode code point is fullwidth
$ npm install --save is-fullwidth-code-point
const isFullwidthCodePoint = require('is-fullwidth-code-point');
isFullwidthCodePoint('谢'.codePointAt());
//=> true
isFullwidthCodePoint('a'.codePointAt());
//=> falseType: number
Code point of a character.
MIT © Sindre Sorhus