How to force a line break in a long word in a DIV?

Use word-wrap:break-word;

It even works in IE6, which is a pleasant surprise.

word-wrap: break-word has been replaced with overflow-wrap: break-word; which works in every modern browser. IE, being a dead browser, will forever rely on the deprecated and non-standard word-wrap instead.

Existing uses of word-wrap today still work as it is an alias for overflow-wrap per the specification.

I am not sure about the browser compatibility

word-break: break-all;

Also you can use the <wbr> tag

(word break) means: "The browser may insert a line break here, if it wishes." It the browser does not think a line break necessary nothing happens.

This could be added to the accepted answer for a 'cross-browser' solution.

Sources:

http://kenneth.io/blog/2012/03/04/word-wrapping-hypernation-using-css/

http://css-tricks.com/snippets/css/prevent-long-urls-from-breaking-out-of-container/

.your_element{
    -ms-word-break: break-all;
    word-break: break-all;

 /* Non standard for webkit */
     word-break: break-word;

    -webkit-hyphens: auto;
       -moz-hyphens: auto;
        -ms-hyphens: auto;
            hyphens: auto;
}

I was just Googling the same issue, and posted my final solution HERE. It's relevant to this question too.

You can do this easily with a div by giving it the style word-wrap: break-word (and you may need to set its width, too).

div {
    word-wrap: break-word;         /* All browsers since IE 5.5+ */
    overflow-wrap: break-word;     /* Renamed property in CSS3 draft spec */
    width: 100%;
}

However, for tables, you also need to apply: table-layout: fixed. This means the columns widths are no longer fluid, but are defined based on the widths of the columns in the first row only (or via specified widths). Read more here.

Sample code:

table {
    table-layout: fixed;
    width: 100%;
}

table td {
    word-wrap: break-word;         /* All browsers since IE 5.5+ */
    overflow-wrap: break-word;     /* Renamed property in CSS3 draft spec */
}

​ is the HTML entity for a unicode character called the zero-width space (ZWSP) which is an invisible character which specifies a line-break opportunity. Similarly the hyphen's purpose is to specify a line-break opportunity within a word boundary.

Found that using the following worked across most major browsers (Chrome, IE, Safari iOS/OSX) except Firefox (v50.0.2) when using flexbox and relying on width: auto.

.your_element {
    word-wrap: break-word;   
    overflow-wrap: break-word;
    word-break: break-word;
}

Note: you may need to add browser vendor prefixes if you are not using an autoprefixer.

Another thing to watch out for is text using   for spacing can cause line breaks mid-word.

Whitespace is preserved by the browser. Text will wrap when necessary, and on line breaks

.pre-wrap {
    white-space: pre-wrap;
    word-break: break-word;
}

DEMO

td { word-break: break-word; white-space: pre-wrap; -moz-white-space: pre-wrap; } table { width: 100px; border: 1px solid black; display: block; }

CSS word-wrap:break-word;, tested in FireFox 3.6.3

Remove white-space: nowrap, if there is any.

Implement:

white-space: inherit;
word-break: break-word;

I solved my problem with code below.

display: table-caption;

From MDN:

The overflow-wrap CSS property specifies whether or not the browser should insert line breaks within words to prevent text from overflowing its content box. In contrast to word-break, overflow-wrap will only create a break if an entire word cannot be placed on its own line without overflowing.

So you can use:

overflow-wrap: break-word;

Can I use?

First you should identify the width of your element. E.g:

#sampleDiv{ width: 80%; word-wrap:break-word; }

so that when the text reaches the element width, it will be broken down into lines.

As mentioned in @davidcondrey's reply, there is not just the ZWSP, but also the SHY ­ ­ that can be used in very long, constructed words (think German or Dutch) that have to be broken on the spot you want it to be. Invisible, but it gives a hyphen the moment it's needed, thus keeping both word connected and line filled to the utmost.

That way the word luchthavenpolitieagent might be noted as lucht­haven­politie­agent which gives longer parts than the syllables of the word.
Though I never read anything official about it, these soft hyphens manage to get higher priority in browsers than the official hyphens in the single words of the construct (if they have some extension for it at all).
In practice, no browser is capable of breaking such a long, constructed word by itself; on smaller screens resulting in a new line for it, or in some cases even a one-word-line (like when two of those constructed words follow up).

FYI: it's Dutch for airport police officer

word-break: normal seems better to use than word-break: break-word because break-word breaks initials such as EN

word-break: normal

.word-break {
   word-break: keep-all;
   word-wrap: break-word;
}

You can use a grid system for this.

<div class="container" style="background-color: green; width: 200px; height: 300px;">
   <div class="row">Thisisatest.Thisisatest.Thisisatest.</div>
   <div class="row">Thisisatest.Thisisatest.Thisisatest.</div>
 </div>

Do this:

<div id="sampleDiv">aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</div>

#sampleDiv{
   overflow-wrap: break-word;
}

just try this in our style

white-space: normal;