I\'m using @font-face to embed fonts in my website. First the text renders as the system default, and then (once the font file has loaded presumably) the correct font render
Edit: The best approach is probably to base64 encode your fonts. This means your font will have to be loaded fully by the time your HTML is parsed and displayed. You can do this with font squirrel's webfont generator https://www.fontsquirrel.com/tools/webfont-generator by clicking "Expert" and then "base64 encode". This is how services like TypeKit work.
Original answer: Another way to detect if fonts are loaded would be using FontLoader https://github.com/smnh/FontLoader or by copying their strategy.
They bind to the scroll event in the browser, because when the font loads it will resize the text. It uses two containing divs (that will scroll when the height changes) and a separate fallback for IE.
An alternative is to check the DOM periodically with setInterval, but using javascript events is far faster and superior.
Obviously, you might do something like set the opacity of body to 0 and then display it in once the font loads.