The Liblouis software suite provides an open-source braille translator, back-translator and formatter for a large number of languages and braille codes. It is a set of libraries designed for use in any of a number of applications, both free and commercial. It is written in C so that it does not require a runtime environment and hence can be used in applications written in high-level languages such as Java and Python.


04 Sep 2017 Liblouis Release 3.3.0

This release brings a slew of Braille table improvements, fixes a number of security related bugs and introduces a new tool to generate liblouis Braille tables based on a corpus of know good Braille translations. For a detailed list of all the changes refer to the list of closed issues.

16 Aug 2017 Liblouis ported to Javascript

We are happy to announce that liblouis now officially supports platforms targeting Javascript. This includes web browsers, javascript-based servers and cross-platform applications.

06 Jun 2017 Liblouis Release 3.2.0

Aside from the usual improvements to Braille tables this release focuses on improving the internal infrastructure. Numerous bugs have been fixed, the CI infrastructure also checks mingw builds now and MSVC compatibility has been massively improved. For a detailed list of all the changes refer to the list of closed issues.

Braille translator and back-translator

Liblouis is an open-source braille translator and back-translator named in honor of Louis Braille. It features support for computer and literary braille, supports contracted and uncontracted translation for many languages and has support for hyphenation. New languages can easily be added through tables that support a rule- or dictionary based approach. Tools for testing and debugging tables are also included. Liblouis also supports math braille (Nemeth and Marburg).

Liblouis has features to support screen-reading programs. This has led to its use in numerous open-source and proprietary screenreaders such as NVDA, Orca, BrailleBack and JAWS. It is also used in some commercial assistive technology applications for example by ViewPlus.

Liblouis is the translator of choice for Benetech’s Bookshare, providing braille access to more than 350,000 books to members worldwide. Bookshare currently offers titles in braille in more than a dozen languages, with the ability to quickly add new languages as translation tables become available.

Liblouis is based on the translation routines in the BRLTTY screenreader for Linux. It has, however, gone far beyond these routines. In Linux and Mac OSX it is a shared library, and in Windows it is a DLL.

Liblouis is free software licensed under the GNU Lesser GPL.

Language bindings

The software has interfaces to a number of programming languages. There are known bindings to C, Python, Java and Javascript.

Braille formatter

Liblouisutdml is an open-source braille formatter. The formatting can be configured via a style sheet. By incorporating Liblouis it provides the capability of translating any XML or plain text file into properly transcribed, embosser-ready braille. This includes translation into grade two, mathematical codes, etc.

Liblouisutdml is free software licensed under the GNU Lesser GPL.

Braille production

There are two braille production systems based on Liblouis and Liblouisutdml.

BrailleBlaster, a joint project between ViewPlus Technologies, American Printing House for the Blind and Abilitiessoft, is aimed at hands-on production where every detail of the Braille is controlled via a graphical user interface.

DAISY Pipeline, backed by the DAISY Consortium, is aimed at automated, hands-off, high-volume production on the server.