RangeError: argument is not a valid code point

Message

JavaScript
RangeError: {0} is not a valid code point (Firefox)
RangeError: Invalid code point {0} (Chrome)

Error type

RangeError

What went wrong?

The String.fromCodePoint() method accepts valid code points only.

A code point is a value in the Unicode codespace; that is, the range of integers from 0 to 0x10FFFF.

Using NaN values, negative Integers (-1), non-Integers (3.14), or values larger than 0x10FFFF (1114111) won't work with this method.

Examples

Invalid cases

JavaScript
String.fromCodePoint('_');      // RangeError
String.fromCodePoint(Infinity); // RangeError
String.fromCodePoint(-1);       // RangeError
String.fromCodePoint(3.14);     // RangeError
String.fromCodePoint(3e-2);     // RangeError
String.fromCodePoint(NaN);      // RangeError

Valid cases

JavaScript
String.fromCodePoint(42);       // "*"
String.fromCodePoint(65, 90);   // "AZ"
String.fromCodePoint(0x404);    // "\u0404"
String.fromCodePoint(0x2F804);  // "\uD87E\uDC04"
String.fromCodePoint(194564);   // "\uD87E\uDC04"
String.fromCodePoint(0x1D306, 0x61, 0x1D307) // "\uD834\uDF06a\uD834\uDF07"

See also

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/javascript/reference/errors/not_a_codepoint

Errors JavaScript RangeError