JSFiddle - React, Tailwind, and code Playground

JavaScript

const body = {profilepic:"data:image/png;base64,abcdefghijklmnopqrstuvwxyz0123456789"};
let mimeType = body.profilepic.match(/[^:]\w+\/[\w-+\d.]+(?=;|,)/)[0];


alert(mimeType);