JavaScript Unescape String

Reading escaped strings

Escape sequences let a string literal contain characters that would otherwise be impossible or confusing to type: line breaks, tabs, quotes and characters from any script in the world. In source code they are a convenience, but when the same strings show up in logs, minified bundles, API responses or error messages, they make the text hard to read. Decoding them reveals the actual content.

JavaScript supports several families of escapes. Single-character escapes such as \n, \t and \ cover common control characters. \xNN gives a character by its two-digit hexadecimal code, \uXXXX by its four-digit UTF-16 code unit, and \u{…} by its full Unicode code point. Emoji and other characters outside the Basic Multilingual Plane appear either as a \u{…} escape or as two \uXXXX surrogates, and both decode to the same character.

The decoder follows the language rules strictly. A backslash before an ordinary character simply yields that character, a backslash at the end of a line continues the string on the next line, and malformed sequences such as \x4 or \u12 are reported with their position instead of being guessed at. Legacy octal escapes, which modern JavaScript forbids, are flagged too.

Decoded text can contain characters that are hard to see: tabs, non-breaking spaces, zero-width spaces and byte-order marks. They are a frequent cause of failed comparisons and odd formatting. The “Show invisible characters” option replaces them with visible markers so you can spot and remove them.

Everything runs in your browser, and nothing is evaluated: the tool reads escape sequences with its own decoder rather than handing the string to the JavaScript engine, so pasting text from untrusted sources is safe.