What is a \uXXXX escape?

It is a way to write a Unicode character using its code point in hexadecimal. \u00E9 represents the letter e with an acute accent, and \u03A9 represents the Greek capital omega. JavaScript, Java and JSON all use this form.

How are emoji and other astral characters handled?

Characters above U+FFFF need either two \uXXXX escapes forming a UTF-16 surrogate pair, or a single \UXXXXXXXX escape. This tool offers both styles, and the decoder reassembles surrogate pairs automatically.

What is the difference between the encoding styles?

The \uXXXX style matches JavaScript and Java and uses surrogate pairs for emoji. The \UXXXXXXXX style matches Python and C. Escape every character forces all text into escapes, which is handy for fully ASCII-safe output.

Can it decode mixed text and escapes?

Yes. The decoder leaves ordinary characters untouched and only converts valid \uXXXX and \UXXXXXXXX sequences, so you can paste a mostly normal string that contains a few escapes.

No. The conversion runs entirely in your browser with JavaScript and nothing is sent to a server.

Unicode \u Escape Encoder & Decoder

The Unicode escape encoder and decoder turns any text into ASCII-safe escape sequences and converts those sequences back into readable characters. It is the standard way to embed accented letters, symbols and emoji inside source code or data files that must stay in plain ASCII.

How it works

Each character has a Unicode code point. Encoding writes that code point in hexadecimal inside a backslash escape. For characters in the Basic Multilingual Plane (up to U+FFFF) the result is \uXXXX with four hex digits. For characters above U+FFFF — most emoji and many historic scripts — there are two choices. The JavaScript and Java form splits the code point into a UTF-16 surrogate pair, written as two \uXXXX escapes. The Python and C form uses a single \UXXXXXXXX escape with eight hex digits.

Decoding scans the text for \u and \U markers, reads the hex digits, and rebuilds the character. When it sees a high surrogate (U+D800–U+DBFF) immediately followed by a low surrogate (U+DC00–U+DFFF), it combines them into the correct astral character. Anything that is not a valid escape is passed through unchanged.

Example

The smiley emoji 😀 is code point U+1F600. Encoded as a UTF-16 surrogate pair it becomes:

😀

Encoded in the Python and C style it becomes the single escape:

\U0001F600

Both decode back to the same emoji. The letter é (U+00E9) is simply é in every style.

Tips

Use the surrogate-pair style for string literals in JavaScript and Java; use \UXXXXXXXX for Python source.
The “escape every character” option is useful when a pipeline only accepts 7-bit ASCII.
Decoding is forgiving: incomplete sequences such as \u12 (only two digits) are left as literal text rather than guessed.