flex-basis
Flexbox and grid
The starting size before growing or shrinking.
| How to write it | flex-basis: auto; |
|---|---|
| Common values | auto, 0, 50% |
| Inherited | No — it stops at this element |
| Part of | flex |
| Category | Flexbox and grid |
How to read this
- An inherited property only needs writing once on the parent — every child picks it up. Most text properties work this way.
- A shorthand resets whatever you leave out. Writing background: red alone also wipes a background image you set earlier.
- When rules collide, the more specific selector wins; only when specificity ties does source order decide.
- Animate transform and opacity for smoothness. Changing width or top forces the layout to be recalculated.
Frequently asked questions
Q. What is the CSS flex-basis property?
The starting size before growing or shrinking.
Q. How do you write flex-basis?
As flex-basis: auto; Common values include auto, 0, 50%.
Q. Is flex-basis inherited?
No. It applies only where you write it, so each element needs its own declaration.
Q. Which shorthand sets flex-basis?
flex can set it in one line.