---
name: "growfs"
section: "8"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["freebsd", "openbsd"]
url: "https://new.carta.tech/growfs"
---

# growfs(8)

grow size of an existing ffs file system

## NAME

**growfs** – grow size of an existing ffs file system

## SYNOPSIS

**growfs** \[**-Nqy**\] \[**-s** *size*\] *special*

## DESCRIPTION

The **growfs** utility extends the [newfs(8)](/newfs/8.md) program. Before starting **growfs**, the partition must be set to a larger size using [disklabel(8)](/disklabel/8.md). The **growfs** utility extends the size of the file system on the specified special file.

Currently **growfs** can only enlarge unmounted file systems. Do not try enlarging a mounted file system - your system may panic and you will not be able to use the file system any longer. Most of the [newfs(8)](/newfs/8.md) options cannot be changed by **growfs**. In fact, you can only increase the size of the file system. Use [tunefs(8)](/tunefs/8.md) for other changes.

The following options are available:

- **-N**

  Test mode. Causes the new file system parameters to be printed out without actually enlarging the file system.

- **-q**

  Operate in quiet mode. With this option, **growfs** will not print extraneous information like superblock backups.

- **-s** *size*

  Determines the *size* of the file system after enlarging in sectors. This value defaults to the size of the raw partition specified in *special* (in other words, **growfs** will enlarge the file system to the size of the entire partition).

- **-y**

  Expert mode. Usually **growfs** will ask you if you have taken a backup of your data and will test whether *special* is currently mounted. The **-y** flag suppresses this, so use this option with great care!

## ENVIRONMENT

- COLUMNS

  If set to a positive integer, output is formatted to the given width in columns. Otherwise, **growfs** defaults to the terminal width, or 80 columns if the output is not a terminal.

## SEE ALSO

[disklabel(8)](/disklabel/8.md), [dumpfs(8)](/dumpfs/8.md), [fdisk(8)](/fdisk/8.md), [fsck(8)](/fsck/8.md), [newfs(8)](/newfs/8.md), [tunefs(8)](/tunefs/8.md)

## HISTORY

The **growfs** utility first appeared in FreeBSD 4.4 and has been available since OpenBSD 3.4.

## AUTHORS

Christoph Herrmann ⟨*chm@FreeBSD.org*⟩ Thomas-Henning von Kamptz ⟨*tomsoft@FreeBSD.org*⟩\
 and the **growfs** team ⟨*growfs@tomsoft.com*⟩

## BUGS

Filesystems must be checked with [fsck(8)](/fsck/8.md) after enlarging.