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This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Avoid using it and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The fontsize() method creates a <font> HTML element that causes a string to be displayed in the specified font size.

Usage note: The <font> element has been removed in HTML5 and shouldn't be used anymore. Instead web developers should use CSS properties.




An integer between 1 and 7, a string representing a signed integer between 1 and 7.

Return value

A string containing a <font> HTML element.


When you specify size as an integer, you set the font size of str to one of the 7 defined sizes. When you specify size as a string such as "-2", you adjust the font size of str relative to the size set in the <basefont> tag.


Using fontsize()

The following example uses string methods to change the size of a string:

var worldString = 'Hello, world';

console.log(worldString.small());     // <small>Hello, world</small>
console.log(worldString.big());       // <big>Hello, world</big>
console.log(worldString.fontsize(7)); // <font size="7">Hello, world</fontsize>

With the object you can get the element's style attribute and manipulate it more generically, for example:

document.getElementById('yourElemId').style.fontSize = '0.7em';


Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'String.prototype.fontsize' in that specification.
Standard Initial definition. Implemented in JavaScript 1.0. Defined in the (normative) Annex B for Additional ECMAScript Features for Web Browsers.
ECMAScript Latest Draft (ECMA-262)
The definition of 'String.prototype.fontsize' in that specification.
Draft Defined in the (normative) Annex B for Additional ECMAScript Features for Web Browsers.

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

Document Tags and Contributors

 Last updated by: fscholz,