IDN2

Section: User Commands (1)
Updated: March 2025
Index Return to Main Contents

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NAME

idn2 - Libidn2 Internationalized Domain Names conversion tool  

SYNOPSIS

idn2 [,OPTION/]... [,STRINGS/]...  

DESCRIPTION

The idn2 tool converts DNS domains from UT-8 to ASCII compatible encoding (ACE) form, as used in the DNS protocol. The encoding format is the Internationalized Domain Name (IDNA2008/TR46) format.

Internationalized Domain Name (IDNA2008) convert STRINGS, or standard input.

Command line interface to the Libidn2 implementation of IDNA2008.

All strings are expected to be encoded in the locale charset.

To process a string that starts with `-', for example `-foo', use `--' to signal the end of parameters, as in `idn2 --quiet -- -foo'.

Mandatory arguments to long options are mandatory for short options too.

-h, --help

Print help and exit

-V, --version

Print version and exit

-d, --decode

Decode (punycode) domain name

-l, --lookup

Lookup domain name (default)

-r, --register

Register label

-T, --tr46t

Enable TR46 transitional processing

-N, --tr46nt

Enable TR46 non-transitional processing

--no-tr46

Disable TR46 processing

--usestd3asciirules

Enable STD3 ASCII rules

--no-alabelroundtrip

Disable A-label roundtrip for lookups

--debug

Print debugging information

--quiet

Silent operation

 

AUTHOR

Written by Simon Josefsson, Tim Ruehsen.  

REPORTING BUGS

Report bugs to: help-libidn@gnu.org
Libidn2 home page: <https://www.gnu.org/software/libidn/#libidn2>
General help using GNU software: <https://www.gnu.org/gethelp/>  

COPYRIGHT

Copyright © 2011-2025 Simon Josefsson, Tim Ruehsen. 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.  

SEE ALSO

idn(1)

The full documentation for idn2 is maintained as a Texinfo manual. If the info and idn2 programs are properly installed at your site, the command

info idn2

should give you access to the complete manual.

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Index

NAME

SYNOPSIS

DESCRIPTION

AUTHOR

REPORTING BUGS

COPYRIGHT

SEE ALSO