macOS
Homebrewverified · 100%
brew install nkflocal Homebrew formula metadata
MacPortsverified · 94%
sudo port install nkfMacPorts ports tree · textproc/nkf/Portfile · source: api.github.com
brew
Install nkf with Homebrew, apt, dnf, MacPorts, Nix, zypper
Network Kanji code conversion Filter (NKF). Version 2.1.5 via Homebrew; verified from local package data.
install
Additional install commands
Linux
Debian aptverified · 92%
sudo apt install libnkf-perlDebian stable package indexes · libnkf-perl · source: deb.debian.org
Fedora dnfverified · 92%
sudo dnf install nkfFedora Rawhide package metadata · nkf · source: dl.fedoraproject.org
Nixverified · 92%
nix profile install nixpkgs#nkfnixpkgs package indexes · pkgs/by-name/nk/nkf/package.nix · source: api.github.com
openSUSE zypperverified · 92%
sudo zypper install nkfopenSUSE Tumbleweed package metadata · nkf · source: download.opensuse.org
overview
Package summary
Network Kanji code conversion Filter (NKF)
Project links
Commands and aliases
- nkf
history
Project history and usage
nkf, the Network Kanji Filter, is a long-lived Japanese text encoding conversion utility. It converts among encodings such as ISO-2022-JP, Shift_JIS, EUC-JP, UTF-8, UTF-16, and UTF-32, with automatic input-encoding guessing as one of its defining conveniences.
Project history
The upstream README credits the original 1987 Fujitsu work by Itaru Ichikawa and the nkf Project's later maintenance from 1996 through 2012. The project's change log shows a major 2.0-era transition in September 2002, including UTF-8/UTF-16 work and migration into SourceForge CVS, which matches nkf's role as Japanese Unix text processing moved from legacy encodings toward Unicode.
Adoption history
nkf has survived because the Japanese encoding problem never fully disappeared: archives, mail, old web content, Windows-31J/CP932 data, and legacy build/test fixtures still need reliable conversion. Homebrew's API reported 144 installs in 30 days, 560 in 90 days, and 4,692 in 365 days when checked on July 1, 2026, and the package is also present across Debian/Ubuntu, Fedora, openSUSE, Nix, MacPorts, and other package systems.
How it is used
Typical command-line use is plumbing: guess an unknown Japanese file's encoding, convert Shift_JIS or EUC-JP to UTF-8, normalize line endings, MIME-decode Japanese mail headers, or do in-place conversion with `--overwrite`. Developers also encounter nkf indirectly through language bindings, notably Ruby's NKF extension.
Timeline
- 1987: original nkf copyright is attributed to Fujitsu Ltd. and Itaru Ichikawa.
- 1996-2012: README credits ongoing nkf Project copyright.
- 2002-09: 2.0-era notes record UTF support work and SourceForge CVS setup.
- 2018-12-15: v2.1.5 is the stable version carried by Homebrew.
Related projects
- Ruby NKF extension
- python-nkf
- iconv
Sources
security posture
Risk level: blue
broad file, network, media, or database tool signal.
Risk classifier
blue risk · medium confidence · tool
Why
- broad file, network, media, or database tool signal
Signals
- text:network
Install behavior
- No Homebrew post-install hook is recorded in formula metadata.
- Homebrew bottle metadata is available for 6 platform targets.
Recommended review
Before unattended agent use, check whether the tool reads plaintext credentials, writes remote state, publishes artifacts, or shells out to plugins.
executables
Installed executables
| Command | Kind | Exposure | Note |
|---|---|---|---|
nkf | cli | global executable |
freshness
Version and freshness
These signals separate page generation age, package-manager activity, and upstream release comparison. Version lag is warned only when an evidence URL and comparable versions are present.
page generated2026-07-08
manager version2.1.5
manager updated
local dataok
upstreamnot checked
latest detectednot detected
- infoNo package-manager update timestamp was available.low confidence
- infoNo cached GitHub release or tag data was available.https://github.com/nurse/nkfnone confidence
install metadata
Package metadata
| Package key | brew:nkf |
|---|---|
| Version | 2.1.5 |
| Package manager | Homebrew |
| Package manager page | https://formulae.brew.sh/formula/nkf |
| Homepage | https://github.com/nurse/nkf |
| Repository | https://github.com/nurse/nkf |
| Upstream docs | https://github.com/nurse/nkf#readme |
| License | Zlib |
| Source archive | https://deb.debian.org/debian/pool/main/n/nkf/nkf_2.1.5.orig.tar.gz |
| Bottle | available (on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, sonoma, x86_64_linux) |
| Homebrew post-install | not defined |
| Service | none declared |
registry facts
Source database details
| Source Database | Homebrew formula API |
|---|---|
| Tap | homebrew/core |
| Full Name | nkf |
| Version Scheme | 0 |
| Revision | 0 |
| Bottle Stable Root URL | https://ghcr.io/v2/homebrew/core |
| Deprecated | no |
| Disabled | no |
| Keg Only | no |
| URL Keys |
|
source database matches
Other package-manager records
Matches are pulled from external package-manager indexes and kept separate from local Automic Vault package links.
Debian apt95%
libnkf-perl 1:2.1.5-1+b8
Network Kanji code conversion Filter for Perl
https://osdn.net/projects/nkf/
sudo apt install libnkf-perl- Section: perl
- Architecture: amd64
- Source Package: nkf
- 3 dependencies
- normalized package name match
- Matched by: Nkf
Debian apt95%
nkf 1:2.1.5-1+b8
Network Kanji code conversion Filter
https://osdn.net/projects/nkf/
sudo apt install nkf- Section: text
- Architecture: amd64
- Source Package: nkf
- 1 dependencies
- normalized package name match
- Matched by: Nkf
Nix95%
nkf
nix profile install nixpkgs#nkf- normalized package name match
- Matched by: Nkf
Ubuntu apt95%
libnkf-perl 1:2.1.5-1build7
Network Kanji code conversion Filter for Perl
https://osdn.net/projects/nkf/
sudo apt install libnkf-perl- Section: universe/perl
- Architecture: amd64
- Source Package: nkf
- 3 dependencies
- normalized package name match
- Matched by: Nkf
Ubuntu apt95%
nkf 1:2.1.5-1build7
Network Kanji code conversion Filter
https://osdn.net/projects/nkf/
sudo apt install nkf- Section: universe/text
- Architecture: amd64
- 1 dependencies
- normalized package name match
- Matched by: Nkf
dnf95%
nkf 2.1.4-38.fc44
A Kanji code conversion filter
sudo dnf install nkf- License: Zlib
- Category: Unspecified
- Architecture: x86_64
- Source Package: nkf
- 2 dependencies
- 1 provides
- normalized package name match
- Matched by: Nkf
dnf95%
perl-NKF 2.1.4-38.fc44
Perl extension for Network Kanji Filter
sudo dnf install perl-NKF- License: Zlib
- Category: Unspecified
- Architecture: x86_64
- Source Package: nkf
- 5 dependencies
- 2 provides
- normalized package name match
- Matched by: Nkf
zypper95%
nkf 2.1.5-1.34
Network Kanji Code Conversion Filter
http://sourceforge.jp/projects/nkf/
sudo zypper install nkf- License: BSD-3-Clause
- Category: System/I18n/Japanese
- Architecture: x86_64
- Source Package: nkf
- 2 dependencies
- 2 provides
- normalized package name match
- Matched by: Nkf
zypper95%
perl-NKF 2.1.5-1.34
Perl extension for nkf (Network Kanji Filter)
http://sourceforge.jp/projects/nkf/
sudo zypper install perl-NKF- License: BSD-3-Clause
- Category: Development/Libraries/Perl
- Architecture: x86_64
- Source Package: nkf
- 3 dependencies
- 2 provides
- normalized package name match
- Matched by: Nkf
MacPorts95%
nkf
sudo port install nkf- normalized package name match
- Matched by: Nkf
source trail
Generated from repository data
This page is generated by av-web from the private package SQLite artifact built by scripts/generate-pkg-sqlite.py.
Combined YAML source
View the package source record on GitHub.
Used sources
- Geiger risk classifier
- Nucleus package database
- av.db category and tag curation
- cross-ecosystem install command graph
- curated package history
- external package-manager database matches
- package relationship graph
- package version freshness
- package-page enrichment