By default, if your tool-tips are larger than the chart width, FusionCharts will automatically wrap them. However, if you want to add manual breaks to the content of your tool-text, you can do so as under:

<chart>
    <set label='John' value='420' tooltext='John Miller{br}Score: 420{br}Rank:2'/>
    <set label='Mary' value='295' tooltext='Mary Evans{br}Score: 295{br}Rank:3'/>
    <set label='Tom' value='523' tooltext='Tom Bowler{br}Score: 523{br}Rank:1'/>
</chart>

In the above XML, to add a line break in the tool-tip, we've used the pseudo code {br}.

When you now see the chart, you'll get the following output:

 
Applying HTML to labels
However, if you want to add line breaks to your data labels, the process is a bit different. Consider the XML below:
<chart>
   <set label='John Miller&lt;BR&gt;Score: 420&lt;BR&gt;Rank:2' value='420' />
   <set label='Mary Evans&lt;BR&gt;Score: 295&lt;BR&gt;Rank:3' value='295' />
   <set label='Tom Bowler&lt;BR&gt;Score: 523&lt;BR&gt;Rank:1' value='523' />
   <styles>
      <definition>
         <style name='myHTMLFont' type='font' isHTML='1' />
      </definition>
      <application>
         <apply toObject='DATALABELS' styles='myHTMLFont' />
      </application>
   </styles>
</chart>

In the above XML, we've first setting label for each <set>. To separate each line we use the <BR> HTML tag. However, since XML cannot use < and >, so we convert <BR> to &lt;BR&gt; . Thereafter, we need to tell FusionCharts that we'll be displaying HTML content in label. So, we create a new font style type with isHTML property set to 1 and then apply it to DATALABELS object.

The above XML will now render the following chart: