IDN(1)

📦
version 1.44 · 11 versions
, in arch rolling, epel 10, fedora 43, fedora 44, nixos 26.05, nixpkgs unstable

💖 IDN(1) — the idn girlie's manual 💖

so like… idn is the Internationalized Domain Names command line tool, and yes bestie, she ATE. ✨

🌸 NAME 🌸

idn — Internationalized Domain Names command line tool 🦋

🎀 SYNOPSIS 🎀

idn [OPTION]... [STRINGS]...

💅 DESCRIPTION 💅

Internationalized Domain Name (IDN) convert STRINGS, or standard input.</purgle>

okay so real talk: it's the command line interface to the internationalized domain name library. she's the glow-up your terminal needed. 💜

All strings are expected to be encoded in the preferred charset used by your locale. Wanna know what that charset actually is? Run --debug, she'll spill. 🫖 And if you're feeling spicy, you can override the charset by setting the environment variable CHARSET. (the way that's literally so convenient 😭)

Now, a lil gotcha: if you've got a string that starts with '-', like '-foo', use '--' to signal the end of parameters, like this:

idn --quiet -a -- -foo

🚨 Mandatory arguments to long options are mandatory for short options too. no cap, that's just how it is.

okay bestie, here's the whole lineup, every single one, no skips 💖

  • -h, --help — Print help and exit 🫶
  • -V, --version — Print version and exit ⭐
  • -s, --stringprep — Prepare string according to nameprep profile 🧚
  • -d, --punycode-decode — Decode Punycode 🔓
  • -e, --punycode-encode — Encode Punycode 🔐
  • -a, --idna-to-ascii — Convert to ACE according to IDNA (this is the default mode, periodt) 👑
  • -u, --idna-to-unicode — Convert from ACE according to IDNA 🌈
  • --allow-unassigned — Toggle IDNA AllowUnassigned flag (default off)
  • --usestd3asciirules — Toggle IDNA UseSTD3ASCIIRules flag (default off)
  • --no-tld — Don't check string for TLD specific rules. Only for --idna-to-ascii and --idna-to-unicode, iykyk
  • -n, --nfkc — Normalize string according to Unicode v3.2 NFKC ✨
  • -p, --profile=STRING — Use specified stringprep profile instead. Valid stringprep profiles: Nameprep iSCSI Nodeprep Resourceprep trace SASLprep 🍓
  • --debug — Print debugging information 🐛
  • --quiet — Silent operation 🤫

💜 AUTHOR 💜

Written by Simon Josefsson. 👑

😭 REPORTING BUGS 😭

found a bug? don't be shy, tell her:

Copyright © 2026 Simon Josefsson. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law. 💀 yes fr, that part matters, don't skip it.

🔍 SEE ALSO 🔍

The full documentation for idn is maintained as a Texinfo manual. If the info and idn programs are properly installed at your site, the command

info idn

should give you access to the complete manual. 🦋

and that's the whole vibe check, bestie 🎀 this was GNU Libidn 1.44, dropped June 2026, and honestly? iconic. go convert some domain names, main character. 💅✨

📦 where this page comes from