Nodejs convert string into UTF-8

I'd recommend using the Buffer object:

var someEncodedString = Buffer.from('someString', 'utf-8').toString();

This avoids any unnecessary dependencies that other answers require, since Buffer is included with node.js, and is already defined in the global scope.

Use the utf8 module from npm to encode/decode the string.

Installation:

npm install utf8

In a browser:

<script src="utf8.js"></script>

In Node.js:

const utf8 = require('utf8');

API:

Encode:

utf8.encode(string)

Encodes any given JavaScript string (string) as UTF-8, and returns the UTF-8-encoded version of the string. It throws an error if the input string contains a non-scalar value, i.e. a lone surrogate. (If you need to be able to encode non-scalar values as well, use WTF-8 instead.)

// U+00A9 COPYRIGHT SIGN; see http://codepoints.net/U+00A9
utf8.encode('\xA9');
// → '\xC2\xA9'
// U+10001 LINEAR B SYLLABLE B038 E; see http://codepoints.net/U+10001
utf8.encode('\uD800\uDC01');
// → '\xF0\x90\x80\x81'

Decode:

utf8.decode(byteString)

Decodes any given UTF-8-encoded string (byteString) as UTF-8, and returns the UTF-8-decoded version of the string. It throws an error when malformed UTF-8 is detected. (If you need to be able to decode encoded non-scalar values as well, use WTF-8 instead.)

utf8.decode('\xC2\xA9');
// → '\xA9'

utf8.decode('\xF0\x90\x80\x81');
// → '\uD800\uDC01'
// → U+10001 LINEAR B SYLLABLE B038 E

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