font-size difference between chrome and firefox using rem

With these it helps In general, don't rely on font sizes. Make your css adopt to the size of the text blocks. Browsers will treat it differently depending on the operating system, user settings and device used. Not everybody will even be able to use the font of your choice.

Hope this helps It has nothing to do with your code. What you see on maximum zoom-out in chrome is just minimum chrome font size. You can set it up in a way explained here . However you can't go below certain value which you can see in your case. And you can't do anything about it. It's considered as a chrome bug: http://code.google.com/p/chromium/issues/detail?id=7417 and there seems to be some workaround, but it will not fix the default chrome behaviour (you'd have to tweak each chrome browser you're viewing the page on). Why do you even care anyway?

it helps some times I know that each browser has default css. , For chrome only css:

@media screen and (-webkit-min-device-pixel-ratio:0) {
    .FontSize  { font-size: 12px; }
}

.FontSize,  x:-moz-any-link  { font-size: 12px; }

like below fixes the issue The browsers don't all support the same font display features yet, unfortunately. If you only use the basics, the fonts will look the same across browsers.

div {
  font: 14px/20px 'Arial', 'Liberation Sans', 'Helvetica Neue', sans-serif;
}

<div>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</div>

div {
  font: 14px/20px 'Arial', 'Liberation Sans', 'Helvetica Neue', sans-serif;
  font-size-adjust: 0.4;
}

<div>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</div>

div {
  font: 14px/20px 'Arial', 'Liberation Sans', 'Helvetica Neue', sans-serif;
  -webkit-text-stroke: 0.7px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility; 
}

<div>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</div>

wish help you to fix your issue I feel there is no use in trying to sort this out. A simple pen at http://codepen.io/anon/pen/dXdwmQ shows that the fonts are rendered differently. Even with reset.css. I'm checking in Windows 7. I think mac renders it correctly.

<link href="httpshttps://cdnjs.cloudflare.com/ajax/libs/meyer-reset/2.0/reset.min.css" rel="stylesheet" />
<style>
  body {
    color: #333;
    font-family: Arial, Helvetica, sans-serif;
    background:#fff;
    font-size: 16px;
  }
</style>

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