This Gist uses a cached, hidden div in order to measure height/width of text. Imperfect since I'm still technically inheriting styles through the body that could affect my offsetWidth and offsetHeight but most likely a better approximation than measuring the width of the "M" character which is often a suggestion when dealing with the lack of hei…

DomMeasureText.js

(function () {
    var _cachedDiv;
    function domMeasureText(text, font) {
        if (!_cachedDiv) {
            _cachedDiv = document.createElement("div");
            _cachedDiv.style.visibility = "hidden";
            _cachedDiv.style.position = "absolute";
            document.body.appendChild(_cachedDiv);
        }

        _cachedDiv.style.font = font;
        _cachedDiv.innerText = text;
        return { width: _cachedDiv.offsetWidth, height: _cachedDiv.offsetHeight };
    }
    this.domMeasureText = domMeasureText;
})()