How do you convert numbers between different bases in JavaScript?

Question

Example: How to convert hexadecimal 8F to decimal?

Answer 1

specify the radix you want to use

parseInt(string, radix) 

parseInt("80", 10) // results in 80
parseInt("80", 16) // results in 128
// etc

Answer 2

The API

To convert to hex:

parseInt(string, radix)

• string: Required. The string to be parsed

• radix: Optional. A number (from 2 to 36) that represents the numeral system to be used

To convert from hex:

NumberObject.toString(radix)

• radix: Optional. Specifies the base radix you would like the number displayed as.

Example radix values: 2 - The number will show as a binary value 8 - The number will show as an octal value 16 - The number will show as an hexadecimal value

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Example Usage

Integer value to hex:

>>> i = 10;
10
>>> i.toString(16);
"a"

Hex string to integer value:

>>> h = "a";
"a"
>>> parseInt(h, 16);
10

Integer value to decimal:

>>> d = 16;
16
>>> d.toString(10);
"16"

Answer 3

Using the parseInt function:

var noInBase10 = parseInt('8F',16);