Comparison table of Basic Suggester and other popular spellchecking software (done in 2007): Apache Java library "Jazzy", web site Dictionary.com, Microsoft Word 2000 and Google.

Test / Feature Basic Suggester Spellcheck
(configured to return 5 suggestions)
Jazzy-0.5.2
Dictionary.com
(web site, top 5 suggestions)
Microsoft Word 2000 Google (web site, search engine suggestion)
Misspelled word test (simple on top to more difficult on bottom)
bnaking banking, bunking, bonking, braking, baking banking, baking, braking, snaking banking, bonking, bunking, banging, baking banking, baking, braking banking
bknaking blanking, banking, bunking, Knacking, bonking No suggestions banking, blanking, bonking, bunking, skanking banking, braking banking
bannking banking, banning, bunking, bonking, blanking banking, banning, banging, bonking, bunking banking, banning banking, banning banking
preduction production, prediction, PR eduction, reduction, predication prediction, production, reduction prediction, production, predication, reduction, predictions production, prediction, reduction production
moscowrussia Moscow Russia, Moscow Russi, Moscow Russian, Moscow Prussia, Rosco Russia massacres moscow russia, moscow-russia, Moss rush, dyscrasia Moscow Russia moscow russia
comparisontable comparison table, comparisons able, comparisons table, companionable No suggestions comparison table, comparison-table, comprehendible comparison table comparison table
semultanieus simultaneous simultaneous simultaneous, smaltines, smaltine's, Sultaness, simultaneity simultaneous simultaneous
sotfwaredevelopmnt software development No suggestions No suggestions No suggestions No suggestions
ecxellentquality excellent quality No suggestions No suggestions No suggestions No suggestions
ecxellentqualety excellent quality No suggestions Argyll and Clyde? No suggestions No suggestions
Other Featuires
Java API Yes Yes No No Yes
Local Service Yes Yes No Yes No
Multiple Languages Yes No No Yes Yes
Custom Dictionary Yes (Advanced version) Yes No Yes No
Context Sensitive* No (Basic Suggester) / Yes (Advanced / Enterprise Suggester) No No Yes (Grammar) Yes
* - Context sensitive spellcheckers are capable of recognizing a misspelled word, even if the word itself is in the dictionary, based on the context of the surrounding words. Without this feature the spellchecker cannot find any abnormality in the following text:
I have a spilling chequer,
It came with my Pea Sea.
It plane lee marks four my revue
Miss Steaks I can knot sea.

Advanced and Enterprise verions of Suggester software allow creating context sensitive spell-checker, which you can test here:
English Spell Check test.

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