zerofree - zero free blocks from ext2, ext3 and ext4 file-systems

Property Value
Distribution Ubuntu 18.04 LTS (Bionic Beaver)
Repository Ubuntu Main amd64
Package name zerofree
Package version 1.0.4
Package release 1
Package architecture amd64
Package type deb
Installed size 25 B
Download size 7.92 KB
Official Mirror
Zerofree finds the unallocated blocks with non-zero value content in
an ext2, ext3 or ext4 file-system and fills them with zeroes
(zerofree can also work with another value than zero). This is mostly
useful if the device on which this file-system resides is a disk
image. In this case, depending on the type of disk image, a secondary
utility may be able to reduce the size of the disk image after
zerofree has been run. Zerofree requires the file-system to be
unmounted or mounted read-only.
The usual way to achieve the same result (zeroing the unused
blocks) is to run "dd" to create a file full of zeroes that takes up
the entire free space on the drive, and then delete this file. This
has many disadvantages, which zerofree alleviates:
* it is slow;
* it makes the disk image (temporarily) grow to its maximal extent;
* it (temporarily) uses all free space on the disk, so other
concurrent write actions may fail.
Zerofree has been written to be run from GNU/Linux systems installed
as guest OSes inside a virtual machine. If this is not your case, you
almost certainly don't need this package. (One other use case would
be to erase sensitive data a little bit more securely than with a
simple "rm").


Package Version Architecture Repository
zerofree_1.0.4-1_i386.deb 1.0.4 i386 Ubuntu Main
zerofree - - -


Name Value
e2fslibs >= 1.37
libc6 >= 2.4


Type URL
Binary Package zerofree_1.0.4-1_amd64.deb
Source Package zerofree

Install Howto

  1. Update the package index:
    # sudo apt-get update
  2. Install zerofree deb package:
    # sudo apt-get install zerofree




2016-11-14 - Thibaut Paumard <>
zerofree (1.0.4-1) unstable; urgency=low
* New upstream release.
* Bug fix: "debian/watch URL needs an update", thanks to
Igor (Closes: #844216).
* Bug fix: "Output not explained", thanks to Joachim Breitner and Tiago
Ilieve (Closes: #778579).
* Fix FTCBFS: Pass triplet-prefixed CC to make, thanks
to Helmut Grohne (Closes: #843218).
* Check against Policy 3.9.8.
2014-03-31 - Thibaut Paumard <>
zerofree (1.0.3-1) unstable; urgency=low
* New upstream release.
* Bug fix: "Typo in package description", thanks to
Pascal De Vuyst (Closes: #698563).
* Check against standards version 3.9.5.
* Update control (maintainer address, VCS fields).
2012-06-13 - Thibaut Paumard <>
zerofree (1.0.2-1) unstable; urgency=low
* New upstream release (includes patch "fillval" from 1.0.1-4).
* Bug fix: "zerofree (1.0.1-4) - please enable hardening flags", thanks
to Dr. Markus Waldeck (Closes: #675905).
* Add build-dep on w3c-dtd-xhtml to work around #676717
2012-04-03 - Thibaut Paumard <>
zerofree (1.0.1-4) unstable; urgency=low
* mention that zerofree works on ext4 file-systes also in the short
2012-04-01 - Thibaut Paumard <>
zerofree (1.0.1-3) unstable; urgency=low
* Bug fix: clarify description and documentation, thanks to Ritesh Raj
Sarraf (Closes: #542360), Christoph Anton Mitterer (Closes: #639301),
Osamu Aoki (Closes: #562171).
* Bug fix: "allow filling empty space with nonzero octets", thanks to
Jacob Nevins (Closes: #600523).
2009-11-25 - Thibaut Paumard <>
zerofree (1.0.1-2) unstable; urgency=low
* Bug fix: "Manpage refers to bogus command 'remount'", thanks
to Ben Finney (Closes: #533606).
* Bug fix: "Description does not contain the word 'unused'",
thanks to Willi Mann (Closes: #504697).
* Check against policy 3.8.3.
* Set DM-Upload-Allowed field.
* Convert to 3.0 (quilt) format.
2008-02-08 - Thibaut Paumard <>
zerofree (1.0.1-1) unstable; urgency=low
* Initial release (Closes: #462091)

See Also

Package Description
zfs-zed_0.7.5-1ubuntu15_amd64.deb OpenZFS Event Daemon
zfsutils-linux_0.7.5-1ubuntu15_amd64.deb command-line tools to manage OpenZFS filesystems
zip_3.0-11build1_amd64.deb Archiver for .zip files
zlib1g-dev_1.2.11.dfsg-0ubuntu2_amd64.deb compression library - development
zlib1g_1.2.11.dfsg-0ubuntu2_amd64.deb compression library - runtime
zsh-common_5.4.2-3ubuntu3_all.deb architecture independent files for Zsh
zsh-dev_5.4.2-3ubuntu3_amd64.deb shell with lots of features (development files)
zsh-doc_5.4.2-3ubuntu3_all.deb zsh documentation - info/HTML format
zsh_5.4.2-3ubuntu3_amd64.deb shell with lots of features