1:1
# 1:1

1:1 may refer to:

* 1:1 scale
* 1:1 correspondence, the same as a set-theoretical bijection
* 1:1 line in a 2-dimensional Cartesian coordinates
* 1:1 aspect ratio (image), the square format
* 1:1 pixel mapping
* 1:1 (film), an animated film by Richard Reeves (2001)
* One to one computing (education)
* Koenigsegg One:1, a model of the Koenigsegg Agera sports car
