substring()

Learn how to use the substring() function to extract a substring from the source string.

Extracts a substring from the source string starting from some index to the end of the string.

Optionally, the length of the requested substring can be specified.

Syntax

substring(source, startingIndex [, length])

Parameters

NameTypeRequiredDescription
sourcestring✔️The string from which to take the substring.
startingIndexint✔️The zero-based starting character position of the requested substring. If a negative number, the substring will be retrieved from the end of the source string.
lengthintThe requested number of characters in the substring. The default behavior is to take from startingIndex to the end of the source string.

Returns

A substring from the given string. The substring starts at startingIndex (zero-based) character position and continues to the end of the string or length characters if specified.

Examples

substring("123456", 1)        // 23456
substring("123456", 2, 2)     // 34
substring("ABCD", 0, 2)       // AB
substring("123456", -2, 2)    // 56