JOrtho - a Java spell-checking library

JOrtho (Java Orthography) is a Open Source spell-checker entirely written in Java. Its dictionaries are based on the free Wiktionary project and can therefore be updated for virtually any language. The library works with any JTextComponent from the Swing framework. This includes JTextPane, JEditorPane and JTextArea.

Table of Contents


What does the library do when it is bound to a JTextComponent?

System Requirements

JOrtho has the following requirements to run smoothly:

What it looks like

There is a small live sample applet of JOrtho where you can test the spelling of a text. You can freely modify this text to get an impression of JOrtho in action.


The free tool and the dictionaries can be downloaded at Logo.

The API is available here. You may also view a live sample.


JOrtho is published under the GNU General Public License (GPL) for inclusion in programs published under a compatible open-source license. If you want to use JOrtho in a commercial product then you can order it in our shop.

If you have further questions on licensing, please contact:


Which languages are supported by JOrtho?

Please have look at the download area at SourceForge.

JOrtho does not support my language. How can I add a language?

Where can I get support for this tool?

Some important words are missing in the dictionary. How can I add them?

Look in the Wiktionary for your language. If the word is missing, then add it. If the word exists, then look at how recent the entry was added/created. We will be creating new dictionaries periodically. It could also be that JOrtho is incorrectly parsing the entry. In this case, please let us know.

Who is responsible for JOrtho?

JOrtho is an Open Source project of i-net software

Creating Dictionaries

File Format

The dictionaries files are a list of words. Every word is saved in a separate line. The word list is saved in UTF8 encoding. The resulting file is compressed with gzip.

Generate dictionaries from Wiktionary

The dictionaries are based on the Wiktionary dictionaries. This is a step by step description how you can generate a new dictionary version.

  1. Download the data from Wiktionary. The file for the English language is Replace the red part with your language. Some languages also require the data of the English Wiktionary (currently Polish and Arabic)
  2. Extract the XML file from the archive
  3. Download or check out the sources of JOrtho and compile it.
  4. Execute the command
    java -Xmx256M com.inet.jorthodictionaries.BookGenerator en <wiktionary folder>
    Replace the red part with your language.


Changes in Version 0.1 (2007-12-13)

Changes in Version 0.2 (2008-01-02)

Changes in Version 0.3 (2008-03-11)

Changes in Version 0.4 (2008-12-05)

Changes in Version 0.5 (2010-06-10)

Changes in Version 1.0 (2013-03-11)