JavaScript: How to remove Last Character from String

This post is a special case of removing a character from a string in JavaScript. If you want a more general explanation about how to manipulate strings, head to that post instead. But if you’re looking specifically to remove the last character from a string, keep reading.

Best Solution: Using slice()

The slice() method extracts parts of a string and returns the extracted parts in a new string. It takes two parameters: the start position, and the end position (end not included). When it’s used with negative integers, slicing will begin from the end of the string.

Here’s how you can use slice() to remove the last character from a string:

let str = "Hello, World!";
str = str.slice(0, -1);
console.log(str); // Outputs: "Hello, World"

Method 2: Using the substring() method

The substring() method is similar to slice(). The difference is that substring() cannot accept negative indexes. To remove the last character from a string, we pass two parameters: 0 (start of the string) and str.length - 1 (one less than the length of the string).

let str = "Hello, World!";
str = str.substring(0, str.length - 1);
console.log(str); // Outputs: "Hello, World"

Method 3: Using the substr() method

The substr() function, not to be confused with substring(), starts extracting from the start index and extracts the specified number of characters. To remove the last character, we use a start index of 0 and a length of str.length - 1.

let str = "Hello, World!";
str = str.substr(0, str.length - 1);
console.log(str); // Outputs: "Hello, World"

Keep in mind that the substr() function is now deprecated. It’s recommended to use one of the other methods to manipulate strings.

Method 4: Using the split() and pop() methods

The split() method divides a string into an ordered list of substrings, puts these substrings into an array, and returns the array. The division is done by searching for a pattern (where the pattern is provided as the first parameter in the method’s call).

The pop() method removes the last element from an array, reduces the length of the array by 1, and returns the removed element. It’s often used when working with arrays.

let str = "Hello, World!";
let chars = str.split(''); // Split the string into an array of characters
chars.pop(); // Remove the last element from the array
str = chars.join(''); // Join the array back into a single string
console.log(str); // Outputs: "Hello, World"

Use cases

Removing the last character from a string in JavaScript is a commonly needed operation. Here are some scenarios where this may be necessary:

1. User Input: Often, users may mistakenly add an extra character such as a space, comma, or period. During form validation, it’s crucial to maintain clean and accurate data, which might necessitate the removal of this additional character.
2. Data Manipulation: At times, while manipulating data, the last character may become redundant. For instance, you might need to remove a trailing punctuation mark when formatting strings or change a file extension.
3. Programming Logic: In certain programming scenarios, like creating a loop that iterates backwards over a string, removing the last character can be part of the logic.