How to Extract a Number from a String With JavaScript

Learn how to extract one or several numbers from a string with JavaScript.

Let’s say you have a string, that includes a number, and you want to extract only the number. No problem, you can use JavaScript’s match() method.

Here’s a string value, containing one number (1995) that is assigned to a variable called stringWithOneNumber:

const stringWithOneNumber = "JavaScript was invented in 1995 by Brendan Eich"

Now let’s attach the match() method to the variable, and add \d+ as an argument, so it looks like this match(/\d+/)

stringWithOneNumber.match(/\d+/)

Note: \d+ is a regular expression (RegEx) meta character that means “match 1 or more digits”.

And let’s print the result:

console.log(stringWithOneNumber.match(/\d+/))
// ["1995"]

It worked!

Extract multiple numbers from a string

What if a string has two or more numbers?

No problem, you just add a global g flag to the match() argument. Let’s use the example from earlier, but this time the string sentence contains two numbers:

const stringWithMultipleNumbers =
  "JavaScript was invented in 1995 by Brendan Eich, and is still used in 2020"

Now add the match() method with \d+ + g:

stringWithMultipleNumbers.match(/\d+/g)

Print the result:

console.log(stringWithMultipleNumbers.match(/\d+/g))
// ["1995", "2020"]

Glorious.