Convert a character to its ASCII code in JavaScript

This post will discuss how to convert a character to its ASCII code in JavaScript.

For example, the ACSII code of 'A' is 65, '0' is 48, 'a' is 97, etc.

1. Using `String.charCodeAt()` function

The charCodeAt() method returns UTF-16 code unit at the specified index. This returns an integer between 0 and 65535. The first 128 Unicode code points (0 to 127) match the ASCII character set.

The following example returns the Unicode value for 'A', which is 65.

var ch = 'A';

var index = 0;

var i = ch.charCodeAt(index);

console.log(i);

Output: 65

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To get the reverse, you can use the fromCharCode() method, which returns a string from a specified sequence of code points.

1	console.log(String.fromCharCode(65, 66)); // returns 'AB'

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2. Using `String.codePointAt()` function

The codePointAt() method returns a number representing the code point value of the character at the given index. The following code returns the Unicode value for 'a', which is 97.

var ch = 'a';

var pos = 0;

var i = ch.codePointAt(pos);

console.log(i);

Output: 97

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It is different from the charCodeAt() method as it can handle code point which cannot be represented in a single UTF-16 code unit (i.e., characters greater than 0xFFFF).

1 2	console.log('????'.codePointAt(0)); // 68181 console.log('\uD800\uDC00'.codePointAt(0)); // 65536

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To do the reverse, you can use the fromCodePoint() method, which returns a string created using the specified sequence of code points.

1	console.log(String.fromCodePoint(68181)); // '????'

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That’s all about converting a character to its ASCII code in JavaScript.

Convert a character to its ASCII code in JavaScript

1. Using String.charCodeAt() function

2. Using String.codePointAt() function

1. Using `String.charCodeAt()` function

2. Using `String.codePointAt()` function