Abstract: Spell Checker project adds spell checking and correction functionality to the windows based application by using autosuggestion technique. It helps the user to reduce typing work, by identifying any spelling errors and making it easier to repeat searches .The main goal of the spell checker is to provide unified treatment of various spell correction. Firstly the spell checking and correcting problem will be formally describe in order to provide a better understanding of these task. Spell checker and corrector is either stand-alone application capable of processing a string of words or a text or as an embedded tool which is part of a larger application such as a word processor. Various search and replace algorithms are adopted to fit into the domain of spell checker. Spell checking identifies the words that are valid in the language as well as misspelled words in the language. Spell checking suggests one or more alternative words as the correct spelling when a misspelled word is identifies.