I’ve found it causes too many problems in complex layouts. Again, you could use the overflow method instead, but it’s not universally ideal. With that in your CSS, all you have to do is add a class of “clearfix” to any element that is “collapsed” due to floated child elements. I can’t remember who originally came up with this, but the most updated and optimized syntax that works in all browsers is the one proposed by Nicolas Gallagher and used in HTML5 Boilerplate. The best method to use to clear floats is the clearfix method. I think the only time I would consider using this one is for a small widget-like box in the page that has floated children (like a tab switcher or something like that), where I know that positioned elements and margins are not going to be a problem. Although this is probably the easiest way to clear floats, it’s really not recommended, because of the problem of scrollbars appearing or child elements being cut off due to positioning, margins, or CSS3 transforms. Using a value of “hidden” or “auto”, the parent will expand to contain all floated children. In this case, at the very least you’ll need to use the overflow property. But instead, you want the parent element to fully contain all the floated children. In this case, you don’t have a trailing element that you can “clear” to fix this. The main problem with floats is what you might refer to as the collapsing container, which causes background elements to disappear. Any value other than “none” will clear the element that you want to follow the float (rather than bump up against it).

The primary way to prevent an element from flowing alongside a floated sibling is to use the clear property. To round this post out, let’s cover the most popular methods for clearing floats. I believe this specification is only a month or two old, so I don’t expect browsers to have support for this any time soon. Regardless of the explanation, you should be able to see that no matter how far browsers advance, they will never clear floats automatically (as the original question seemed to assume) - because the behaviour of floats is not a bug it’s a feature.Īs Scott points out in the comments, it looks like there will indeed be an easy way to clear floats, using the contain-floats value for the min-height property. I prefer to say that floats are taken out of the normal flow in relation to sibling block elements. So it seems that floats should have a different wording ascribed to them. The only problem I have with the W3C definition is that it sounds like it’s talking about absolutely positioned elements. This is what floats do: They cause other floated elements and inline content to flow around the float, but other block boxes ignore the float. Notice that the green box is acting as if the red box is not even there, rather than “flowing” around it like the text does. You can see this behaviour demonstrated in the JS Bin below: Here is, in part, how the W3C spec explains what floats do:Ĭontent flows down the right side of a left-floated box and down the left side of a right-floated box … Since a float is not in the flow, non-positioned block boxes created before and after the float box flow vertically as if the float didn’t exist. Instead, we want to be able to use a better method.īut clearing floats are a fact of developer lives today, and so I thought I’d explain why clearing them is still necessary, even in “modern” browsers. The eventual goal of CSS layouts is to never need to use floats for layout.

This doesn’t mean, though, that clearing floats will always be necessary. And it’s still needed in so-called “modern” browsers (assuming you’re using floats for layout). If you’re new to CSS, then it would seem that the answer to this question should be “yes, of course - modern browsers don’t have these types of bugs!” But the necessity to clear floats is not a browser bug it’s actually, well, more of a CSS feature. If I understand it right clear float is automatic in most modern browsers right? The other day, someone asked me the following question:

Overflow hidden meaning