ASCII transliterations of Unicode text

unicode, c, unidecode
pip install cunidecode==0.0.2



lossy ASCII transliterations of Unicode text

It often happens that you have text data in Unicode, but you need to represent it in ASCII. For example when integrating with legacy code that doesn't support Unicode, or for ease of entry of non-Roman names on a US keyboard, or when constructing ASCII machine identifiers from human-readable Unicode strings that should still be somewhat intelligible (a popular example of this is when making an URL slug from an article title).

In most of these examples you could represent Unicode characters as "???" or "\15BA\15A0\1610", to mention two extreme cases. But that's nearly useless to someone who actually wants to read what the text says.

What Unidecode provides is a middle road: function unidecode() takes Unicode data and tries to represent it in ASCII characters (i.e., the universally displayable characters between 0x00 and 0x7F), where the compromises taken when mapping between two character sets are chosen to be near what a human with a US keyboard would choose.

The quality of resulting ASCII representation varies. For languages of western origin it should be between perfect and good. On the other hand transliteration (i.e., conveying, in Roman letters, the pronunciation expressed by the text in some other writing system) of languages like Chinese, Japanese or Korean is a very complex issue and this library does not even attempt to address it. It draws the line at context-free character-by-character mapping. So a good rule of thumb is that the further the script you are transliterating is from Latin alphabet, the worse the transliteration will be.

Note that this module generally produces better results than simply stripping accents from characters (which can be done in Python with built-in functions). It is based on hand-tuned character mappings that for example also contain ASCII approximations for symbols and non-Latin alphabets.

This is a C port of Unidecode by Paul Logston <>

Unidecode (by Tomaz Solc) is a Python port of the Text::Unidecode Perl module by Sean M. Burke <> and later

Module content

The module exports a single function that takes an Unicode object (Python 2.x) and returns a string:

>>> from cunidecode import unidecode
>>> unidecode(u'ko\u017eu\u0161\u010dek')
>>> unidecode(u'30 \U0001d5c4\U0001d5c6/\U0001d5c1')
'30 km/h'
>>> unidecode(u"\u5317\u4EB0")
'Bei Jing '


Python 2.x >= 2.6 and a C compiler/linker.

This implementation of unidecode does not "decode" characters outside of the Basic Multilingual Plane. A Python build with "wide" Unicode characters may lead to a segmentation fault if an attempt to decode a character outside the BMP is made.

Surrogate pair encoding of "narrow" builds is not supported.


You install Unidecode, as you would install any Python module, by running these commands:

python install
python test


You can get the latest development version of cUnidecode with:

git clone


Questions, bug reports, useful code bits, and suggestions for Unidecode should be sent to

Questions, bug reports, useful code bits, and suggestions for cUnidecode should be sent to


Original character transliteration tables:

Copyright 2001, Sean M. Burke <>, all rights reserved.

Python code and later additions to Unidecode:

Copyright 2014, Tomaz Solc <>

C code and later additions to cUnidecode:

Copyright 2014, Paul Logston <>

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. The programs and documentation in this dist are distributed in the hope that they will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.