JS String Methods Reference

A free, example-driven reference for the string side of the JavaScript language. Every article pairs the exact API signature with runnable snippets and the small gotchas that bite people in production: UTF-16 surrogate pairs, locale quirks, and off-by-one errors.

• String.prototype.charCodeAt

  UTF-16 code units, indexing semantics, and when the number you get back is not a character.

• String.prototype.codePointAt

  Reading whole Unicode code points, including emoji and symbols outside the BMP.

• fromCodePoint and the code point model

  Building strings from numeric code points and how UTF-16 encodes them internally.

• Understanding Unicode in JavaScript

  Escape sequences, normalization forms, and comparing strings safely.