Replace/Remove all Numbers in a String using JavaScript

# Replace/Remove all Numbers in a String using JavaScript

Use the String.replace() method to replace or remove all numbers in a string, e.g. const replaced = str.replace(/[0-9]/g, '!');.

The String.replace() method will return a new string with all numbers replaced by the provided replacement.

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const str = 'b234 h567 c890';

// ✅ Replace each number in a string with a replacement string
const replaced = str.replace(/[0-9]/g, '!');
console.log(replaced); // 👉️ b!!! h!!! c!!!

// ✅ Replace multiple, consecutive numbers with a single replacement string
const replaced2 = str.replace(/[0-9]+/g, '!');
console.log(replaced2); // 👉️ b! h! c!

If you need to remove all numbers from the string, specify an empty string as the replacement.

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// ✅ Remove all numbers from the string
const str = 'b234 h567 c890';

const replaced = str.replace(/[0-9]/g, '');
console.log(replaced); // 👉️ b h c

The String.replace() method returns a new string with one, some, or all matches of a regular expression replaced with the provided replacement.

The method takes the following parameters:

Strings are immutable in JavaScript.

The forward slashes / / mark the beginning and end of the regular expression.

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const str = 'b234 h567 c890';

const replaced = str.replace(/[0-9]/g, '!');
console.log(replaced); // 👉️ b!!! h!!! c!!!

The square brackets [] are called a character class. The character class in the example matches all numbers in the range 0 to 9.

We used the g (global) flag because we want to match all occurrences of a number in the string, and not just the first occurrence.

# Replace multiple, consecutive numbers with a single replacement

If you want to replace multiple, consecutive numbers with a single replacement string, use the plus + special character.

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const str = 'b234 h567 c890';

const replaced2 = str.replace(/[0-9]+/g, '!');
console.log(replaced2); // 👉️ b! h! c!

The plus + special character matches the preceding item (any digit) 1 or more times.

# You can use any replacement character

The example uses an exclamation mark as the replacement, however, you could use any other replacement string, e.g. an underscore.

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const str = 'a1 b2 c3';

const replaced = str.replace(/[0-9]/g, '_');
console.log(replaced); // 👉️ a_ b_ c_

As previously noted, if you simply need to remove all numbers from the string, specify an empty string as the replacement.

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const str = 'b234 h567 c890';

const replaced = str.replace(/[0-9]/g, '');
console.log(replaced); // 👉️ b h c

We remove all numbers from the string by replacing them with empty strings.

If you have to do this often, define a reusable function.

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function replaceNumbers(string, replacement) {
  return string.replace(/[0-9]/g, replacement);
}

// 👇️ a^ b^ c^
console.log(replaceNumbers('a1 b2 c3', '^'));

// 👇️ a_ b_ c_
console.log(replaceNumbers('a1 b2 c3', '_'));

# Replace/Remove all numbers in a String using \d special character

You can also use the \d special character to replace all numbers in a string.

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const str = 'b234 h567 c890';

// ✅ replace all occurrences of a number with a replacement string
const replaced = str.replace(/\d/g, '_');
console.log(replaced); // 👉️ b___ h___ c___

// ✅ replace multiple, consecutive numbers with a single replacement string
const replaced2 = str.replace(/\d+/g, '_');
console.log(replaced2); // 👉️ b_ h_ c_

If you need to remove all numbers from the string using this approach, specify an empty replacement string.

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const str = 'b234 h567 c890';

// ✅ remove all numbers from a string
const replaced = str.replace(/\d/g, '');
console.log(replaced); // 👉️ b h c

The \d special character matches any digit in the range 0 to 9.

You can adjust the replaceNumbers() function to use the \d special character if you find it more readable.

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function replaceNumbers(string, replacement) {
  return string.replace(/\d/g, replacement);
}

// 👇️ a^ b^ c^
console.log(replaceNumbers('a1 b2 c3', '^'));

// 👇️ a_ b_ c_
console.log(replaceNumbers('a1 b2 c3', '_'));

The function takes a string and a replacement as parameters and replaces each occurrence of a number with the provided replacement.

Which regex you find more readable is a matter of personal preference. I'd use the character class [0-9] because I find it more intuitive than the \d special character.

Alternatively, you can use the String.match() method.

# Remove all Numbers from a String using String.match()

This is a two-step process:

1. Use the String.match() method to match all non-digit characters in the string.
2. Use the Array.join() method to join the array of matches without a separator.

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const str = 'b234 h567 c890';

// 👇️ [ 'b', ' ', 'h', ' ', 'c' ]
console.log(str.match(/\D/g));

const replaced = str.match(/\D/g, '').join('');
console.log(replaced); // 👉️ b h c

We used the String.match() method to match all non-digit characters in the string.

The only argument we passed to the method is a regular expression.

The \D special character matches any character that is not a digit.

The method returns an array containing all non-digit characters from the string.

The last step is to use the Array.join() method to join the array of matches into a string without a separator.

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const str = 'b234 h567 c890';

// 👇️ [ 'b', ' ', 'h', ' ', 'c' ]
console.log(str.match(/\D/g));

const replaced = str.match(/\D/g, '').join('');
console.log(replaced); // 👉️ b h c

The Array.join() method concatenates all of the elements in an array using a separator.

The only argument the Array.join() method takes is a separator - the string used to separate the elements of the array.

If a value for the separator argument is omitted, the array elements are joined with a comma ,.

We used an empty string separator to join the array of non-digits into a string without a separator.

If you have to do this often, extract the logic into a reusable function.

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function removeNumbers(string) {
  return string.match(/\D/g, '').join('');
}

// 👇️ a b c
console.log(removeNumbers('a1 b2 c3'));

// 👇️ a b c
console.log(removeNumbers('a123 b234 c345'));

The function takes a string as a parameter and removes all numbers from the string.

If you ever need help reading a regular expression, check out this regular expression cheat sheet by MDN.

It contains a table with the name and the meaning of each special character with examples.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

• Remove special Characters from a String in JavaScript
• How to Remove a Substring from a String in JavaScript
• How to Remove a Trailing Slash from a String in JavaScript
• Remove the Vowels from a String in JavaScript