---
name: "rev"
section: "1"
platform: "linux"
package: "util-linux"
version: "2.42.4-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "freebsd", "openbsd", "macos"]
url: "https://new.carta.tech/rev"
---

# rev(1)

reverse lines characterwise

## NAME

rev - reverse lines characterwise

## SYNOPSIS

**rev** \[option\] \[*file*...\]

## DESCRIPTION

The **rev** utility copies the specified files to standard output, reversing the order of characters in every line. If no files are specified, standard input is read.

This utility is a line-oriented tool and it uses in-memory allocated buffer for a whole wide-char line. If the input file is huge and without line breaks then allocating the memory for the file may be unsuccessful.

## OPTIONS

- **-0**, **--zero**

  *Zero termination*. Use the byte '\\0' as line separator.

- **-h**, **--help**

  Display help text and exit.

- **-V**, **--version**

  Display version and exit.

## SEE ALSO

[**tac**(1)](/tac/1.md)

## REPORTING BUGS

For bug reports, use the *issue tracker* \<https://github.com/util-linux/util-linux/issues\>.

## AVAILABILITY

The **rev** command is part of the util-linux package which can be downloaded from *Linux Kernel Archive* \<https://www.kernel.org/pub/linux/utils/util-linux/\>.