Dan Herbert Dan Herbert - 16 days ago 4x
CSS Question

Can I stop 100% Width Text Boxes from extending beyond their containers?

Lets say I have a text box that I want to fill a whole line. I would give it a style like this:

input.wide {display:block; width: 100%}

This causes problems because the width is based on the content of the text box. Text boxes have margin, borders, & padding by default, which makes a 100% width text box larger than its container.

For example, here on the right:

enter image description here

Is there any way to make a text box fill the width of its container without expanding beyond it?

Here is some example HTML to show what I mean:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<title>Untitled Page</title>
<style type="text/css">
#outer{border: 1px solid #000; width: 320px; margin: 0px;padding:0px}
#inner{margin: 20px; padding: 20px; background: #999;border: 1px solid #000;}
input.wide {display:block; margin: 0px}
input.normal {display:block; float: right}
<div id="outer">
<div id="inner">
<input type="text" class="wide" />
<input type="text" class="normal" />
<div style="clear:both;"></div>

If this is run, you can see by looking at the "normal" text box that the "wide" text box is sticking out beyond the container. The "normal" text box floats to the actual edge of the container. I'm trying to make the "wide" text box fill its container, without expanding beyond edge like the "normal" text box is.


What you could do is to remove the default "extras" on the input:

input.wide {display:block; width:100%;padding:0;border-width:0}

This will keep the input inside its container. Now if you do want the borders, wrap the input in a div, with the borders set on the div (that way you can remove the display:block from the input too). Something like:

<div style="border:1px solid gray;">
 <input type="text" class="wide" />

Edit: Another option is to, instead of removing the style from the input, compensate for it in the wrapped div:

input.wide {width:100%;}

<div style="padding-right:4px;padding-left:1px;margin-right:2px">
  <input type="text" class="wide" />

This will give you somewhat different results in different browsers, but they will not overlap the container. The values in the div depend on how large the border is on the input and how much space you want between the input and the border.