# The PreviewHTML output processor¶

The options below control the operation of the PreviewHTML output processor that is run when you include "output/PreviewHTML" in the jax array of your configuration or load a combined configuration file that includes the PreviewHTML output jax. They are listed with their default values. To set any of these options, include an PreviewHTML section in your MathJax.Hub.Config() call. For example

MathJax.Hub.Config({
PreviewHTML: {
scale: 120
}
});


would set the scale option to 120%.

scale: 100

The scaling factor (as a percentage) of math with respect to the surrounding text. The PreviewHTML output processor tries to match the ex-size of the mathematics with that of the text where it is placed, but you may want to adjust the results using this scaling factor. The user can also adjust this value using the contextual menu item associated with the typeset mathematics.

minScaleAdjust: 50

This gives a minimum scale (as a percent) for the scaling used by MathJax to match the equation to the surrounding text. This will prevent MathJax from making the mathematics too small.

mtextFontInherit: false

This setting controls whether <mtext> elements will be typeset using the math fonts or the font of the surrounding text. When false, the font for mathvariant="normal" will be used; when true, the font will be inherited from the surrounding paragraph.

linebreaks: {}

This is an object that configures automatic linebreaking in the PreviewHTML output. In order to be backward compatible with earlier versions of MathJax, only explicit line breaks are performed by default, so you must enable line breaks if you want automatic ones. The object contains the following values:

automatic: false

This controls the automatic breaking of expressions: when false, only linebreak="newline" is processed; when true, line breaks are inserted automatically in long expressions.

width: "container"

This controls how wide the lines of mathematics can be.

Use an explicit width like "30em" for a fixed width. Use "container" to compute the size from the containing element. Use "nn% container" for a portion of the container. Use "nn%" for a portion of the window size.

The container-based widths may be slower, and may not produce the expected results if the layout width changes due to the removal of previews or inclusion of mathematics during typesetting.