OpenTaal ("Open Language") is a Dutch foundation which provides free Dutch language files to be used in open-source software spell checking, hyphenation, thesaurus and grammar checking.
The new spelling rules laid down in it are compulsory in government and education of participating countries since August 2006.
OpenTaal provides files for spelling check which are being used in software such as OpenOffice.org, Firefox,[4] Thunderbird,[5] Safari, Opera, TinyMCE and more.
The Dutch Language Union[7] has approved OpenTaal's word list and labelled it with Keurmerk Spelling.
Also OpenTaal has been granted funding by the Dutch Language Union to implement missing functionality in Hunspell.