How to get the length of the string as bytes in Nodejs?

September 24, 2020 - 1 min read

To get the string length in bytes in Node.js, you can use the byteLength() method in the Buffer class.

Let's say you have a string called Hello World!,

// string
const str = "Hello World!";

Now let's use the Buffer.byteLength() to get the bytes of the string.

// string
const str = "Hello World!";

// get string length in bytes
const bytes = Buffer.byteLength(str, "utf-8");

console.log(bytes); // 12
  • The method accepts types of Buffer, String, etc as the first argument.
  • The second argument is the encoding, the default is utf-8.
  • The method returns the size of the bytes as an integer.

See this example live in

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