--- title: byteSize tags: string,beginner --- Returns the length of a string in bytes. - Convert a given string to a [`Blob` Object](https://developer.mozilla.org/en-US/docs/Web/API/Blob). - Use `Blob.size` to get the length of the string in bytes. ```js const byteSize = str => new Blob([str]).size; ``` ```js byteSize('😀'); // 4 byteSize('Hello World'); // 11 ```