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As of today, this is what we – David and Sagi – are doing FULL TIME.

CSS3 gave us the wonderful property, text-overflow, which can do things like create ellipsis and gracefully cut off words. However, text-overflow has a serious limitation: it only works on a single line of text.

.block-with-text {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    // don’t forget that .block-with-text can’t be an inline element
}

A few days ago I had to truncate a multiline block of text. It’s a common problem, but I was a disappointed because we still don’t have a simple, cross-browser CSS solution for it. I tried a few ideas, but each time I found that the ‘…’ wasn’t quite right. Sometimes it appeared far from the end of the text or fell over to the next line.

Finally I found the ideal solution.

What are the options?

In order to fully understand why this pure CSS solution is so awesome, I want to run through a few of the alternatives and the problems with each.

If you’d like, you can jump ahead to check out a live example of the solution: codepen demo.

1. -Webkit-line-clamp property

I really like this for it’s simplicity, but unfortunately it is not cross browser (doesn’t work in Firefox and Internet Explorer). I hope that in future we will have a regular, non-vendor-prefixed CSS property.

To use -webkit-line-clamp, add the following to your CSS:

.block-with-text {
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;  
}

2. Text-overflow: -o-ellipsis-lastline

As of version 10.60, Opera added the ability to clip text on multi-line blocks. To be honest I have never tried this property, but it allows you to use -webkit-line-clamp.

3. Using JavaScript

Here’s a simple Javascript function for truncating text, but it has some serious drawbacks.

#block-with-text { 
    height: 3.6em; 
}

function ellipsizeTextBox(id) {
    var el = document.getElementById(id);
    var wordArray = el.innerHTML.split(' ');
    while(el.scrollHeight > el.offsetHeight) {
        wordArray.pop();
        el.innerHTML = wordArray.join(' ') + '...';
     }
}
ellipsizeTextBox(‘block-with-text);

Some of the drawbacks of this method include requiring the block of text to have a fixed height, not waiting for the font to load and the possibility that the ‘…’ will appear on the next line after the main text.

4. Truncate the text on the server

This is an example of truncating the text in PHP. This method works fine in limiting the text, but requires messing with the server-side just to deal with presentation, which is supposed to the be the job of CSS.


$text = 'your long long text';
$maxPos = 100;
if (strlen($text) > $maxPos)
{
    $lastPos = ($maxPos - 3) - strlen($text);
    $text = substr($text, 0, strrpos($text, ' ', $lastPos)) . '...';
}

A Simple, Pure CSS Solution

Clearly none of these options are perfect. I wanted an easier and more bulletproof way to handle this, so I found that we can truncate text using two carefully placed CSS pseudo elements.

Here’s the full CSS. We’ll walk through the code below.

/* styles for '...' */ 
.block-with-text {
  /* hide text if it more than N lines  */
  overflow: hidden;
  /* for set '...' in absolute position */
  position: relative; 
  /* use this value to count block height */
  line-height: 1.2em;
  /* max-height = line-height (1.2) * lines max number (3) */
  max-height: 3.6em; 
  /* fix problem when last visible word doesn't adjoin right side  */
  text-align: justify;  
  /* place for '...' */
  margin-right: -1em;
  padding-right: 1em;
}
/* create the ... */
.block-with-text:before {
  /* points in the end */
  content: '...';
  /* absolute position */
  position: absolute;
  /* set position to right bottom corner of block */
  right: 0;
  bottom: 0;
}
/* hide ... if we have text, which is less than or equal to max lines */
.block-with-text:after {
  /* points in the end */
  content: '';
  /* absolute position */
  position: absolute;
  /* set position to right bottom corner of text */
  right: 0;
  /* set width and height */
  width: 1em;
  height: 1em;
  margin-top: 0.2em;
  /* bg color = bg color under block */
  background: white;
}

How It Works

Let’s imagine that we need to contain a block of text to a max of 3 lines. In order to do so, we have to handle the following cases:

1. The text is more than 3 lines

more-3-lines

The pseudo element :before with ‘…’ is in the right corner

Here, the text is justified, so you won’t ever see this gap

2. The text is less than 3 lines

less-3-lines

3. The text is exactly 3 lines

3lines

Benefits

  • 1. Pure CSS
  • 2. Responsive
  • 3. No need to recalculate on resize or font’s load event
  • 4. Cross browser

A couple things to watch out for

Unfortunately this solution also has some drawbacks:

  • 1. We need to have a plain background color for covering up the ‘…’ if the text is less than the max number of lines.
  • 2. we need some space for ‘…’, and if the parent block has overflow: hidden or overflow: auto then we need to remove style margin-right: -1em;.

Also for the patient reader, I created an SCSS mixin to do this faster:
codepen demo

/* mixin for multiline */
@mixin multiLineEllipsis($lineHeight: 1.2em, $lineCount: 1, $bgColor: white){
  overflow: hidden;
  position: relative;
  line-height: $lineHeight;
  max-height: $lineHeight * $lineCount; 
  text-align: justify;
  margin-right: -1em;
  padding-right: 1em;
  &:before {
    content: '...';
    position: absolute;
    right: 0;
    bottom: 0;
  }
  &:after {
    content: '';
    position: absolute;
    right: 0;
    width: 1em;
    height: 1em;
    margin-top: 0.2em;
    background: $bgColor;
  }
}

.block-with-text {
  @include multiLineEllipsis($lineHeight: 1.2em, $lineCount: 3, $bgColor: white);  
}

What do you think? Do you have another solution for multiline text truncation? Let me know in the comments.

About Natalia Onischuk

Front-end developer at SimilarWeb. Likes skiing, kitesurfing, books and ternary operators.