Spelling Plus Library (SPL)

Check-as-you-type spell checking for Flex, Flash, and AIR

Spelling Plus Library (SPL) is a full featured client-side spell checking engine, designed to be used in Flash, Flex and AIR; by both developers and designers. It was built as a best of breed library, with careful attention to architecture, optimization, and extensibility.

February 27th, 2013: SPL is now open source. You can get the source here: https://github.com/gskinner/SPL. Or read the full announcement on our blog.

Sample Usage: Right click words for spelling suggestions. Note that loading and parsing the word list takes a few seconds.

highlighter = new SpellingHighlighter(richTextEditorInstance.textArea);


The full real-time spelling and highlighting engine is under 30kb (only 5kb for the dictionary logic). Our proprietary condensed and compressed word list format is equally tiny, fitting over 150,000 words in under 250kb.


In Flash, simply drag components on stage to use SPL. In Flex, use simple MXML tags. No code is required to enable real-time spellchecking on your text fields and components.


SPL has a robust, fully documented, and extremely flexible ActionScript 3 API, designed with extensibility in mind.


Custom dictionaries. Custom underline patterns. Configurable case handling. Editable locale strings. Virtually everything can be easily customized.


Check and highlight over 25,000 words per second*. Parse a 150,000 word dictionary in less than 3 seconds. Generate spelling suggestions in 250ms (or just 25ms in fast mode).


Support for accented characters. Background loading. Polite word list parsing (won't stall your application). Intelligent highlighting of visible text. Case sensitivity. Support for contractions. Works with custom context menus.

* With 5% misspelling rate. Benchmarked on a 2ghz Intel CPU.