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What is the difference between position: relative, absolute, fixed, and sticky?
What is the difference between position: relative, absolute, fixed, and sticky?
Jun 30, 2025 am 01:03 AM
The position attribute has four values: relative, absolute, fixed, and sticky, and their behaviors are different. 1. relative: The element is offset from its original position and is still in the document flow; 2. absolute: detached from the document flow, positioned relative to the nearest positioning ancestor elements; 3. fixed: detached from the document flow, always positioned relative to the viewport, keeping the position unchanged when scrolling the page; 4. sticky: between relative and fixed, according to the scroll position switching behavior, you need to specify top, bottom and other values ??to take effect, which are often used to fix the table header or sidebar.
When you're working with CSS positioning, the values relative , absolute , fixed , and sticky can be confusing at first. They all do different things and behave differently depending on the context. Let's break it down in a straightforward way.
How position: relative works
This one is often misunderstood because it doesn't move an element out of the document flow like some others do. When you set position: relative on an element, you can shift it from where it would normally sit without taking it completely out of layout .
For example:
.box {
position: relative;
top: 20px;
left: 10px;
} This moves the .box 20px down and 10px to the right from its original spot , but other elements around it still act like it's in its original place.
Use this when you want to nudge an element slightly without messing up the overall layout.
What position: absolute really means
This one takes the element completely out of the document flow . That means it won't affect how other elements are laid out anymore.
But here's the catch: it positions itself relative to the nearest positioned ancestor — that means any parent that has a position value other than static (which is the default).
If there's no such ancestor, it goes all the way up to the viewport or even <html> in some cases.
A common use case:
- Dropdown menus inside a container.
- Icons or toolsets positioned precisely within a component.
So if you're trying to align something absolutely inside a box, make sure that box has position: relative (or another non-static value) — otherwise, your absolutely positioned item might show up somewhere unexpected.
The behavior of position: fixed
This one acts a lot like absolute , except it always positions relative to the viewport , not any parent.
That means when you scroll the page, a fixed element stays stuck to the same spot on the screen.
Common uses:
- Navigation bars that stick to the top while scrolling.
- Floating action buttons on mobile sites.
Example:
.navbar {
position: fixed;
top: 0;
width: 100%;
}This keeps the navbar visible at the top no matter how much the user scrolls.
One thing to watch out for: fixed elements can sometimes overlap content if you're not careful with spacing (like adding padding to the body so the main content isn't hidden behind the nav bar).
Understanding position: sticky
Sticky is kind of a hybrid. It behaves like relative until a certain scroll point, then switches to fixed .
You have to define at least one of top , bottom , left , or right for it to work properly.
Use cases:
- Sidebars that stick as you scroll.
- Table headers that stay visible while scrolling through rows.
Example:
.header {
position: sticky;
top: 0;
}This makes the header stick to the top of the viewport once the user scrolls past it.
Important notes:
- Sticky only works inside containers that aren't using
overflow: hidden,transform, orfilter. - It also needs room to scroll — if the parent doesn't allow vertical scrolling, sticky won't activate.
So, to recap the differences quickly:
-
relative: shifts element from its normal spot, stays in flow. -
absolute: positions relative to nearest positioned ancestor, out of flow. -
fixed: positions relative to the viewport, always stays put when scrolling. -
sticky: starts relative, becomes fixed after a scroll threshold.
Basically that's it.
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