BetterCSS

Inset is shorthand for top, right, bottom, and left. It pins absolutely positioned elements to edges.

When to use

Full-bleed overlays, centered modals, and filling a relative parent edge to edge.

Core concepts

  • Each side can be a length, percentage, or auto.
  • Equal values on all sides collapse to the inset shorthand.
  • absolute inset-0 is the classic full-bleed overlay pattern.

Class combinations

Utilities stack. These recipes do more together than any single class alone. Try them after you've explored the sandbox above.

  • Full overlay

    absolute inset-0

    Pins all four edges to the containing block. Common for modal backdrops and cover layers.

  • Dead center

    absolute inset-0 m-auto size-48

    inset-0 stretches the box; auto margins + explicit size center it without flex or transform.

Summary

  • inset is shorthand for top, right, bottom, and left on positioned elements: one declaration instead of four.
  • inset: 0 is the classic full-bleed overlay pattern for modals, drawers, and cover layers.
  • Individual sides still override shorthand when you need asymmetric pinning, like bottom-right toast placement.
  • inset only works when position is absolute, fixed, or sticky. static and relative ignore these offsets for layout.
  • Tailwind exposes inset utilities as inset-*, top-*, right-*, bottom-*, left-* with arbitrary values when needed.