JSFiddle - React, Tailwind, and code Playground
HTML
<div id="calculated"></div>
<div id="rendered"></div>
<br />
<span>Hello World</span>
CSS
span{
font:30px Arial;
}
JavaScript
function get_tex_width(txt, font) {
this.element = document.createElement('canvas');
this.context = this.element.getContext("2d");
this.context.font = font;
return this.context.measureText(txt).width;
}
$("#calculated").html('Calculated width ' + get_tex_width("Hello World", "30px Arial"));
$("#rendered").html("Span text width "+$("span").width());